東漢末年，宦官專政，外戚爭權，政治腐敗，大姓豪族獨霸經濟，壟斷教育，軍閥殘暴，官吏貪污。民間起義層出不窮，公元184年，太平清道首領張角率領黃巾軍起義"七州二十八郡同時俱發。""天下響應，京師震動"。東漢王朝發動各路大軍鎮壓。在參加鎮壓的隊伍中，騎都尉曹操因軍功突出，戰後被任為濟南相;孫堅因軍功被任為別部司馬;劉備也因軍功被任為安喜縣尉。
在鎮壓黃巾軍後，全國被地的軍閥所割據，無處不在混戰。
以曹操為宰相的東漢政府統一了中國北部。曹操控製了中央政府。220 年曹操的兒子曹丕奪得政權，把皇帝劉協趕下寶座，建立魏王朝。
一年後，以皇族自居的劉備在四川建立蜀漢王朝，又明年，孫權在武昌建立吳王朝。成三國鼎立。史稱三國。
三國（狹義220年－280年，廣義184年、190年或208年－280年）是中國歷史上的一段時期，有魏、漢、吳三個國傢。漢末三國戰爭不斷，使得人口下降，經濟受損，三國皆重視經濟發展。由於戰爭需求，各種技術都有較大發展。
三國時期開始的時間學者各有不同見解，一般分成狹義及廣義。狹義是220年曹丕逼東漢獻帝禪讓，建國曹魏，使東漢滅亡開始。廣義一般認為有184年東漢黃巾之亂開始。這源自漢靈帝為解决黃巾之亂而成立州牧制度，該制度導致地方割據，天下分裂。其他觀點還有：190年董卓挾漢獻帝離開洛陽開始，這時東漢朝廷已經崩潰；208年赤壁之戰後開始，這時三國鼎立形成雛型。歷史學家多註重三國鼎立的形成與過程，自184年東漢已開始失去政權實體、群雄割據，形成三國雛型直到魏代漢為止，所以往往將這段184年到220年的時間納入三國時期加以討論。
三國時期人才輩出，後世常常追思當時風雲人物。在唐宋詩詞中出現大量三國內容。元明清期間，三國事跡更加深入人心，成為戲劇和民間藝術文學常見話題。明代羅貫中以這段歷史為藍本，編撰歷史小說《三國演義》成為了中國四大名著之一。其豐富多彩的歷史內涵也流傳到亞洲及世界各地，影響了這些地區。晉代陳壽所作《三國志》，後經裴鬆之註引，頗有參考價值。直到今天，三國的著名人物、事件仍是耳熟能詳，成為電視、電影或遊戲題材之一。
更有三國題材小說《鬥轉星斜》被翻拍成電視劇。
三國局面的形成
189年，漢靈帝駕崩，劉辯繼位被立為少帝。執政的何太後之兄何進聯絡袁紹，殺宦官蹇碩。紹、進等密謀盡殺宦官，並召董卓入洛陽為援。當宦官殺何進，而紹又殺盡宦官之時，卓率兵入洛陽，盡攬朝政。他廢黜少帝，另立劉協為帝，即漢獻帝。卓之專橫激起了東漢朝臣和地方牧守的反對，釀成大規規模的內戰。卓入洛陽後，紹出奔冀州，橋瑁假藉朝廷三公名義，要求州郡興兵討伐卓，關東州郡紛紛響應。他們分屯要害，推紹為盟主，相機進攻卓。190年，卓避關東兵鋒，挾持獻帝西遷長安。關東聯軍彼此欺詐並吞，不久就分崩離析了。193年長安兵變，卓被殺，關中混亂不已。經過激烈的混戰以後，到196年時，全國形成許多割據區域：袁紹占據冀、青、並三州，操占據兗、豫二州，韓遂、馬騰占據涼州，公孫瓚氏遼東，陶謙、劉備、呂布先後占據徐州，袁術占據揚州的淮南部分，劉表占據荊州，劉璋占據益州，孫策占據揚州的江東部分，士燮占據交州。此外，張魯以道教的組織形式保據漢中地區，置祭酒以治民。在這些割據者中，勢力最強也最活躍的是袁紹和曹操。卓入洛陽後，曹操逃至陳留，聚兵反抗，成為關東聯軍的一支。他在濟北誘降黃巾軍三十萬衆，選其精銳，編為青州兵；又陸續收納一些豪強地主武裝。建安元年，他把獻帝遷到許縣，取得了奉天子以令不臣之勢；屯田續資。200年，曹、袁兩軍進行官渡之戰，操以弱勝強，全殲袁軍主力；又利用紹二子的矛盾攻占袁氏的鄴城，相繼占領青、冀、幽、並四州之地，統一了北方大部。207年，曹軍出盧竜塞，打敗侵擾北方的烏桓。208年，曹軍南下，攻占劉表之子劉琮所據的荊州。依托於荊州的劉備嚮南奔逃。魯肅受孫權之命與備會晤，商討對策，諸葛亮又受備之命，於柴桑與孫權結盟，共抗曹軍。孫、劉聯軍以少勝多，大敗曹軍於赤壁，迫使曹軍退回中原。促使形成三國鼎立局面。操北歸以後，用兵於關中、隴西，把統一範圍擴及整個北方，不久曹操自封魏王。211年，備率部進入益州，逐步占據了原來劉璋的地盤。219年，備從曹軍手中奪得漢中，關羽也嚮曹軍發起進攻，但是孫權遣軍襲殺關羽，占領荊州大部，隔三峽與劉備軍相持。 222年，漢軍出峽與吳軍相持於夷陵，猇亭一戰，被吳將陸遜擊敗，退回蜀中。猇亭之戰以後不久, 蜀、吳恢復結盟關係，共抗曹魏，至此，三國鼎立局面正式形成。南北之間雖然還常有戰事發生，有時規模還比較大，但是總的說來，力量大體平衡，鼎足之勢維持了四十餘年之久。
三國簡介
魏
隨着漢丞相曹操對北方的統一和屯田製、租調製的施行，北方社會趨於穩定，生産逐漸恢復。政府修整道路，興建水利，便利了交通和槽運。恢復的冶鐵業中，水排得到推廣，絲織業也興盛起來。商品交換漸有起色，魏明帝時重新頒用錢幣。洛陽、鄴城都日趨繁華。曹操進駐冀州後頒行租調製。建安二十一年，曹操稱魏王，建立魏國。220年正月，曹死；十月，子曹丕稱帝，國號魏，都洛陽，建元黃初。魏得北方。魏置司、豫、兗、青、徐、涼、雍、冀、幽、並、荊、揚等州。其中涼州領戊己校尉護西域；幽州地境達於遼東；南部諸州大致依秦嶺、淮河分別與漢、吳相接，魏有戶六十六萬餘，人口四百四十餘萬；魏建立不久，政權開始腐敗。齊王芳在位時發生了輔政的宗室曹爽和太尉司馬懿的權力之爭。曹爽重用名士三狗及李勝、畢軌、等人，改易朝典，排斥懿。司馬氏是東漢以來的世傢大族，懿本人又富於謀略，屢有軍功。238年，他率軍平定公孫淵，使遼東歸入魏版圖。249年，又乘曹爽奉齊王芳出洛陽城謁高平陵的機會發動政變，逼迫爽屈服，並處死爽及其黨羽，獨攬朝政，史稱高平陵事變。後來，懿及子司馬師、司馬昭陸續壓平了起自淮南的王凌（251年）、毋丘儉（255年）、諸葛誕（257年）的軍事叛亂和其他朝臣的反抗，鞏固了司馬氏的統治。以竹林七賢為代表的一批玄學名士對司馬氏持消極反抗態度，其中的嵇康被司馬氏以非毀名教和欲助毋丘儉為亂之罪名殺害。他們之中的大部分在魏和西晉初都陸續歸服於司馬氏。當反抗力量都被消滅以後，司馬氏趁時立功，於263年出兵滅漢。兩年後，司馬炎以接受禪讓為名，代魏為晉。歷五帝，共四十六年。
魏皇帝 曹丕 曹睿 曹芳 曹髦 曹奐
廟號 謚號 封號 名字 在位時間
無 高皇帝 無 曹騰
無 太皇帝 無 曹嵩
太祖 武皇帝 魏王 曹操 （魏國締造者，216年稱王，在位4年）
世祖 文皇帝 無 曹丕 （魏國建立者，220年稱帝，在位7年）
烈祖 明皇帝 無 曹睿 （226年即位，在位13年）
無 魏哀帝齊王（厲公） 昭陵縣公 曹芳 （239-254 在位15年）
無 廢帝 高貴鄉公 曹髦 （254-260 在位6年）
無 元皇帝 陳留王 曹奐 （260-265 在位6年）
漢
（史學稱之為【季漢】、【蜀漢】）
188年，漢宗室劉焉出任益州牧。焉死，子璋繼任。焉、璋相繼壓平了當地豪強的反抗。207年，劉備邀諸葛亮為輔佐，提出“隆中對”戰略思想。211年璋邀請劉備入蜀，使擊保據漢中的張魯。214年，備占據益州；219年進駐漢中，自稱漢中王。是年，留守荊州的關羽被孫權軍襲殺。221年，備在成都稱帝，國號漢，世稱蜀，又稱蜀漢，建元章武。漢置益州，自秦嶺至於南中。有戶二十八萬，口九十四萬，吏四萬，兵十萬餘；備為爭奪已失的荊州，於次年出峽，夷陵之戰，敗退入蜀，病死白帝。劉禪繼立。備死，亮輔劉禪。小國弱民，處境睏難。西南夷接連叛亂。益州郡豪強雍闓執太守，求附於吳。牂柯太守朱褒、越嶲太守高定都響應雍闓，南中地區動亂擴大。225年，亮南徵，亮軍西平越嶲，馬忠軍東平牂柯，然後與中路李恢所部共指益州郡。此時孟獲已代雍闓據郡。亮敗獲，並按馬謖“攻心為上”對孟獲七擒七縱，終使獲歸心，南中平定。亮把夷人渠帥移置成都為官，把南中青羌編為軍隊，並允許大姓招引夷人作部麯；以南中的牛馬特産充實漢國軍資。西南夷人地區的閉塞狀態，從此有所改變。南中戰爭結束，漢吳結盟也取得圓滿成果。亮227年率軍進駐漢中，同魏展開爭奪關隴的激戰。亮在益州疲憊情況下急於求戰，一方面力圖以北伐來鞏固“興復漢室，還於舊都”的正統地位；一方面則以攻為守，藉以圖存。228年，諸葛亮北伐開始。以後三年，亮又屢次北伐，都由於軍糧不濟，沒有成果。234年再次北伐，進軍渭水南面的五丈原，病死軍中，漢軍撤回，北伐停頓。亮死後，蔣碗、費禕、董允等人相繼為相，因循守成而已。258年以後，宦官擅權，政治腐敗。姜維北伐，勞而無功。263年，魏滅蜀之戰開始，年鼕滅漢。歷二帝，共四十三年。
漢皇帝
廟號 謚號 封號 名字 在位時間
無 漢昭烈帝 蜀先主 劉備 (開國皇帝221-223 在位2年)
無 孝懷皇帝 蜀後主 劉禪 (223-263 在位41年)
吳
黃巾起義時，孫堅隨朱儁到中原鎮壓黃巾，後轉戰於涼州和荊州江南諸郡。董卓之亂時，堅參加討伐董卓的關東聯軍，隸屬於袁術，在淮南活動，堅死，子策統領部衆，約於 194年開始嚮江東發展。得到周瑜等人的助力，驅逐劉繇，逼降王朗。196年獻帝遷許以後，策拒術而聯曹操，受封為吳侯。199年，策擊破廬江太守劉勳，吞併其部，並取得豫章郡地。200年策死，策弟孫權統衆。208年權由吳徙治京城。籌劃赤壁之戰，勢力達於荊州；210年招附士夑兄弟，取得東南半壁。211年權徙治秣陵，次年，改秣陵為建業。219年權破關羽，占有荊州全境。夷陵之戰勝利，限製了漢出峽發展的可能。229年，權稱帝，遷都建業，建立吳國。有揚、荊、交三州。有戶五十二萬餘，口二百三十萬，吏三萬餘，兵二十三萬。權尚存的睏難，一是對付山越的不寧，一是在巢湖地區抗拒曹魏的壓力。東南州郡山區的山越人，阻險割據，甚至北聯曹魏，反對孫權勢力嚮南方內地擴張。權與山越進行過多次戰爭，屢獲勝利，234年諸葛格率軍進攻丹陽山越，經三年圍困，山越十萬人出山投降，其中四萬丁壯補兵，餘下的成為編戶。孫吳統治的幾十年中，山越人大體與漢人趨於融合。權主要軍事活動在淮南。赤壁之戰後，曹操軍屢攻合肥地區，雙方互有勝負。江北居民多渡江，瀕江數郡成為空虛地帶。諸葛亮死，魏漢戰爭停止，魏加強淮南對吳的進攻。吳軍除沿江設督駐軍、遍置烽燧以外，還在巢湖南口築濡須塢，嚴密防守。魏水師有限，進攻難於奏效，魏吳相持有年。權統治時，江東經濟有顯著發展。北人南來，山越出居平地，勞動力增多。長江兩岸地區都設有屯田區，其中毗陵屯田區。會稽郡農業生産比較發達。歷代陸續修成的浙東運河和江南運河在孫吳時發揮了通航效益。江南運河雲陽至京口一段流經山間，不便通航，未得到修整。雲陽以西開闢破岡瀆，使秦淮河和江南運河聯通，為三吳至建業的便捷水道。絲織業開始在江南興起，但織造技術還不高，蜀錦成為重要的輸入物資。銅鐵冶鑄繼承東漢規模而有發展規律，青瓷業也在東漢釉陶製造基礎上走嚮成熟。由於河海交通的需要，造船業很興旺，海船經常北航遼東，南通南海諸國。230年萬人船隊到達夷洲，這是大陸與臺灣聯繫的最早記錄，吳使臣朱應、康泰泛海至林邑、扶南諸國。大秦商人和林邑使臣也曾到達建業。江南文化的提高，出現了一批知名的經學家和文史之士。佛教開始在江南傳播，居士支謙從洛陽南來，世居天竺的康僧會稍晚從交趾北上。他們在建康譯經傳法，影響頗大。道教在南方民間繼續流傳。孫吳諸將以私兵隨孫氏徵戰，孫吳屢以國傢佃客賜給功臣，功臣往往擁有多至於數縣的俸邑，因而逐漸形成武將世襲領兵的制度。同時，江南也出現了像吳郡的顧、陸、朱、張那樣的占有大量土地和童僕，而且各有門風，世居高位的大族。他們和世襲領兵的武將同是孫吳政權的主要支柱。權死後吳日趨衰弱，而魏在司馬氏消滅淮南地區三次軍事叛亂後日趨強大。司馬氏以先滅漢後取吳作為國策，而在滅漢、代魏後又忙於新朝定製，吳政權暫得延續。269年，羊祜命王瀎在益州籌建水師，並預定攻吳的軍事方略。279鼕，晉滅吳之戰開始，280三月攻下建業，孫皓降，吳亡。歷四帝，共五十二年。
吳皇帝 孫權 孫休 孫亮 孫皓
廟號 謚號 封號 名字 在位時間
無 武烈皇帝 烏程候 孫堅
無 長沙桓王 吳候 孫策
太祖 大皇帝 無 孫權 (公元229年稱帝，建立吳國。在位23年)
無 會稽王 無 孫亮 (252-258 在位6年)
無 景皇帝 無 孫休 (258-264 在位6年)
無 文皇帝 無 孫和
無 無 烏程候 孫皓 （264～280 在位17年）
三國的發展
三分雛型
208年，曹操統一北方後率大軍南下，嚮荊州進攻，而劉表也在此時病死，其次子劉琮接位並嚮操投降，劉備見此，决定離開新野，南下江陵，途中被曹軍追上擊敗，逃至夏口。此時魯肅到備處探聽情況，備也派諸葛亮出使到江東，雙方結盟，孫劉聯軍以弱勝強，操退回北方。權、備雙方也開始各自爭奪荊州。備嚮荊南施壓，成功逼降荊南四郡；而權部將瑜也嚮荊州南郡發兵，用了很長時間，最終攻剋南郡。權為嚮備示好，將其妹嫁給備。而權為拓展勢力，占據了交州。其後，瑜曾想出兵攻打益州，但在途中病逝。魯肅接替其位，並將南郡藉給備。而操在南方戰爭失敗，轉移嚮西發展，操欲進攻漢中張魯，西涼諸軍閥疑其將攻擊自己，在 211年起兵，共推馬超、韓遂為首領，操率軍鎮壓，成功將西北一帶收為領地。
三國鼎立
劉備受到益州之主劉璋邀請，入蜀幫助璋防守張魯、曹操的入侵，備口頭答應，但入蜀後不斷收買人心，雙方最終在212年决裂，備調兵直指成都的璋，雖然其間軍師龐統中流矢死，但仍於214年成功逼使璋投降，備成功入主益州，留下關羽防衛荊州。同時，操曾南下攻擊孫權，最後雙方撤退。215年，操快速地得到漢中，而同時孫劉兩傢開始爭奪荊州擁有權而發生戰鬥，兩軍對壘。但備得悉操得漢中，危害蜀地安全，便和權平分荊州，回師益州，但雙方關係經已惡化。216年操就任魏王，一年後，備進攻漢中，而操內部有守將叛亂，權也偷襲合肥，漢中成功落入備之手，操雖曾揮軍要奪回，但都不成功。219年，備自封漢中王。同年，羽率荊州軍北上攻魏，但主戰、剛接魯肅之位的呂蒙突襲荊州，並擒殺羽。220年，操死，曹丕登位，並逼漢獻帝禪讓，建國號魏；而於221年，備在成都稱帝，國號漢；權嚮魏稱臣，而丕封權為吳王，加九錫。同年，備以報羽之仇為名東徵權，權派出接替呂蒙的陸遜迎戰。結果備慘敗，不久病死於白帝。223年，劉禪登位，漢吳再度結盟，最終魏漢吳三國鼎立局面形成。229年，吳王權稱帝，建立吳。
三分歸晉
263年，司馬昭派鐘會、鄧艾、諸葛緒分兵三路南平蜀漢，與蜀漢將領姜維發生拉鋸戰，魏軍被擋於劍閣前，鄧艾避開維大軍的鋒芒，抄陰平小路直取涪城，進逼成都，漢主劉禪投降，漢被魏所滅。及後會、維在蜀發生叛變，三國志記載，“魏將士奮發,殺會及維,維妻子皆伏誅”,可見並未引起大亂，昭快速平定。265年，昭死後，司馬炎奪取魏政權，定都洛陽，建立晉朝，史稱西晉，並開始籌備伐吳。279年，炎兵分六路，由北、西嚮東吳進發，吳主孫皓曾想抵抗，但在暴政的統治下，士兵毫無戰意，晉軍勢如破竹。280年，晉軍成功攻剋建業，皓投降，吳滅亡，西晉成功統一天下。
三國的主要戰役
宛城之戰:東漢獻帝建安二年,曹操徵荊州，來到宛城，張綉迎降。曹操甚為歡悅。但因曹操納了其叔嫂鄒氏，感到受辱而起兵造反，用賈詡之計成功偷襲了曹軍，導致曹操的愛將典韋、長子曹昂、侄子曹安民等人戰死，兵馬損失慘重。
易京之戰： 袁紹於此戰中基本統一河北,再無後顧之憂,意欲南嚮以爭天下。並於第二年發動官渡之戰。
官渡之戰： 袁紹勢力衰退，曹操統一北方成為最有實力的諸侯。
赤壁之戰： 曹操統一全國的計劃挫敗，劉備趁亂得荊州，形成三分局勢的雛型。
潼關之戰： 掃蕩馬超等西涼豪傑,鞏固了後方勢力,曹操真正意義上的統一北方。
夷陵之戰： 使蜀漢國力大衰，無力奪回荊州，形成三國鼎立最後形態。
合肥之戰： 吳魏之戰，結果魏勝吳敗，曹操以後就沒有到過吳了。
諸葛亮、姜維北伐： 雙方互有勝負，同時導致蜀漢國力消耗，間接導致蜀漢亡國。
魏滅蜀之戰： 使蜀漢滅亡。鄧艾、鐘會、姜維及一些蜀國遺臣在叛亂中被殺。
晉滅吳之戰： 孫吳滅亡，三國時代結束，西晉統一中國。
三國大事年表
184年 2月 黃巾起義。
10月 張角病死。
11月 起義主力失敗
189年 4月 靈帝卒，皇子劉辯即位。何太後臨朝，大將軍何進秉政。
8月 何進誅殺宦官，被張讓等所殺。袁紹盡誅宦官。董卓進京。
9月 董卓廢少帝劉辯為弘農王，立九歲的陳留王劉協為帝，是為獻帝。
12月 操號召各鎮諸侯共起討伐董卓。
190年 1月 各路諸侯起兵反卓。卓令李儒毒死弘農王 ，卒年15。
2月 卓焚洛陽，遷都長安，洛陽古都殘破。公孫度自立為遼東侯。
191年 孫堅破卓，斬華雄。袁紹奪州牧韓馥的冀州，自領州牧。曹操任東郡太守。
192年 4月 王允設連環計，呂布殺董卓。
6月 傕、汜圍長安，殺允，敗布。操敗青州黃巾軍，收編為“青州兵”，實力壯大。堅擊表，戰死。
193年 操東徵徐州，大敗陶謙。
194年 布擊操。謙病亡，備領徐州牧。
195年 2月 李傕、郭汜相攻。李傕劫持獻帝，郭汜扣押公卿。
7月 獻帝出長安東歸，李傕、郭汜領兵追之。
10月 操領兗州牧。孫策攻江東大敗劉繇。
196年 7月 獻帝在楊奉等人護送回長安。
9月 操始興屯田，將獻帝劫持到許。布攻劉備，劉備投操。
197年 1月操伐張綉，敗。 袁術在壽春稱帝。
9月，曹操攻袁術，大敗。
198年 9月 布攻打備，破小沛。
12月 操擒殺布。周瑜同小喬成親。
199年 3月，袁紹攻殺公孫瓚占領冀、幽、青、並四州。
6月 備討伐術，術病死。
11月 綉降操。董承與王子服等密謀除操。策襲取廬江，敗劉勳。
200年 1月，操誅殺承等。策遇刺身亡，孫權繼位。陳琳撰寫討操檄文，官渡之戰開始。
10月 操偷襲烏巢。
201年 4月 操敗紹於倉亭。備奔劉表。
202年 5月 紹病亡。少子尚嗣位。
9月 曹操攻袁譚，袁尚救譚，大敗。
203年 權討伐黃祖。
204年 操平定冀州。遼東公孫度死，子公孫康繼位。
205年 操平定青州。
206年 操平定並州。
207年 8月 操大破烏桓，滅袁氏殘餘勢力，統一北方。備三顧茅廬請諸葛亮。操從匈奴贖回蔡文姬。
208年 6月 操封為漢丞相。
7月 操南徵表。
8月 表病死。操殺孔融。
9月 劉琮降操。
11月 赤壁之戰，操被孫劉聯軍打敗。
209年 10月 備與權之妹成親。
210年 操建成銅雀臺。瑜亡。公孫康遣公孫模、張敞等興兵伐韓、濊，建帶方郡。
211年 操攻破馬超。備入川。
212年 5月 曹操殺馬騰。
10月 操南下進攻濡須口。備駐紮葭萌關。權移治秣陵，改名建業。
213年 5月 獻帝封操為魏公，加九錫。
214年 5月 權攻破皖城。
7月 權進攻合肥，被張遼擊敗。
10月 夏侯淵平定隴右。
11月 獻帝、伏後與國丈伏完密謀除操，事泄，操誅殺衆人。劉璋降備，備自領益州牧。
馬超降劉備。
215年 7月 操徵張魯。
11月 魯降操。逍遙津之戰。操濡須敗權。
216年 曹操自稱魏王。鼕，曹操南徵孫權。
217年 2月 操進攻濡須口，權敗。
218年 1月 少府耿紀、司直韋晃、太醫令吉平等於許都起事反曹，失敗被殺。
曹彰大破烏桓軍，鮮卑部落投降，北方平定。
219年 1月 劉備進兵定軍山，黃忠擊斬夏侯淵。
3月 曹操至漢中，與劉備相持數月，退軍而還。
7月 劉備稱漢中王。關羽水淹七軍。
10月 羽失荊州，被權害。
220年 1月 操病亡。
7月 蜀將孟達降曹。
10月 丕稱帝，建魏國。
12月 魏以洛陽為京師 ，長安、譙、許昌、鄴城、洛陽為五都。
221年 4月 備稱帝。
7月 備伐吳。張飛遇害。
222年 權稱吳王。
6月 彝陵之戰，陸遜火燒連營，大敗備。
9月 魏攻吳，吳軍據之。
12月 孫權派遣使者與劉備通好。
223年 4月 備死於白帝城，禪繼帝位。
8月 丕五路伐蜀。蜀吳重修和好。雍闓叛亂。
224年 曹丕率軍攻吳，至廣陵，臨江而還。
225年 亮南徵。亮七擒七縱孟獲，平定蜀南方。
226年 丕病亡，曹睿繼位。
12月 曹睿封司馬懿為驃騎大將軍。權圍攻江夏，兵敗。
227年 亮上書北伐。
228年 亮一伐中原。姜維降蜀。馬謖失街亭。周魴詐降誘魏攻吳，陸遜大敗曹休。亮二伐中原。
229年 權稱帝。亮三伐中原。
230年 吳派衛溫、諸葛直航海到夷洲。亮四伐中原。曹真病亡。
231年 亮第五伐中原。
232年 魏遼東太守公孫淵遣使嚮吳稱臣。
233年 吳大舉攻魏合肥。遣將軍全琮攻六安，皆不剋而還。
234年 亮六出祁山。
8月 亮病逝於五丈原。 吳三路攻魏，魏明帝親自率軍救合肥，吳軍退走。
235年 1月 曹睿封懿為太傅。馬鈞製造司南車和水轉百戲。
237年 遼東公孫淵自立為燕王。
238年 5月頃 魏明帝遣劉昕、鮮於嗣取帶方、樂浪
8月 懿平遼東，殺公孫淵。日本邪馬臺女王卑彌呼派使者到魏，魏封卑彌呼“親魏倭王”。
239年 1月 曹睿亡，曹芳繼位。
240年 蜀將張嶷平定蠻族之亂。魏帶方太守弓遵遣梯俊赴倭。
241年 魏在淮河興修水利。
242年權派軍攻打海南島。高句麗東川王位宮叛，寇西安平。
244年 曹爽派兵攻打蜀不利，傷亡慘重。
8月 幽州刺史毋丘儉從玄菟出發攻高句麗
9月 百濟臣智襲取樂浪邊民，後懾太守劉茂威歸還
10月 魏軍攻剋丸都，東川王奔沃沮
11月 毋丘儉以王頎東追至挹婁界，劉茂、弓遵別遣伐濊
245年 吳太子孫和與魯王孫霸爭權，陸遜因受牽連，憂憤而死。
5月 魏軍各路徵伐高句麗的軍隊皆告捷，毋丘儉刻石紀功並凱旋。
246年 毌丘儉兩破高句麗。
247年 蜀將維出隴右攻魏，接應附蜀的羌、鬍部落。王頎繼任帶方太守，遣張政攜詔書、黃幢等赴倭。
248年 懿封為丞相。
249年 1月 懿殺曹爽一夥。夏侯霸降蜀。維伐魏。
250年 權廢孫和為庶人，魯王孫霸賜死，立孫亮為太子。維攻魏西平失敗。
251年 魏太尉王凌陰謀叛變，被懿平定。
7月 懿亡。
252年 懿長子司馬師為大將軍。權亡，孫亮繼位。司馬昭攻吳，失敗。
253年 諸葛恪進攻魏，無功而返。維攻魏狄道失敗。吳孫峻誅殺恪。
254年 9月 師廢曹芳。
10月 曹髦繼位。吳孫英謀殺孫峻未果。
255年 鎮東將軍毌丘儉與揚州刺史文欽討伐師。師亡。昭為大將軍。維攻魏狄道，先勝後敗。
256年 4月，昭討伐諸葛誕。維伐魏被鄧艾擊敗。吳孫峻死，弟孫琳專吳政。孫綝殺滕胤等人。
257年 誕與孫吳聯合起兵反魏。維出駱𠔌攻魏失敗。
258年 魏軍破壽春，斬誕。孫綝廢吳帝孫亮為會稽王，立琅琊王孫休為帝。孫休與丁奉設計殺綝。
260年 5月 賈充、成濟弒曹髦。
6月 曹奐繼位。
262年 10月， 維攻魏，被鄧艾擊敗，退屯沓中。
263年 昭三路伐蜀，蜀亡。
264年 鐘會維密謀失敗被殺。昭稱晉王。孫休亡，孫皓繼位。
265年 8月 昭亡，其子司馬炎繼任晉王。
9月 吳末帝遷都武昌。
12月 炎廢奐為陳留王，自稱晉武帝，建立西晉，魏亡。
266年 吳揚州諸郡之民逆流供給武昌，勞役繁重，怨聲載道。12月 吳末帝還都建業。
271年 吳皓出兵攻晉，因士兵怨恨而止。
272年 炎派楊肇、羊祜等率軍支持戰略要地西陵。陸抗大敗楊肇，殺步闡。
276年 2月 東夷八國歸化
7月 東夷十七國內附
277年 晉文鴦擊破鮮卑人。
278年 羊祜死、杜預駐紮襄陽。
2月 東夷六國來獻
279年 西晉出六路兵馬攻打吳。
280年 西晉滅吳，皓降，吳亡。
三國時期的文化
學術思想
漢晉之際的學術思想發生劇烈的變動，主要受傳統思想的變化與政治鬥爭有關，前者成份居大。由尚交遊、重品藻，反動而變為循名責實，歸於申韓。因尚名務虛偽反動而為自然、率直，歸於老莊。
由於東漢晚期政治敗壞，局勢混亂。曹操與諸葛亮采用名傢或法傢的思想來恢復社會秩序。曹操提倡信賞必罰，主張法治。提出“用人唯才”的觀念打破以門第或名教的標準。諸葛亮也提倡法治觀念，入蜀後修明法製，執法公平。提出“治國之要，務在舉賢”的主張以任纔適用。他也重視軍法，如街亭之戰馬謖違反軍令而被斬，他也自貶三等。漢末魏初的名法思想為此後魏晉玄學思潮提供了基礎，使名士基於政治黑暗將焦點由名法的具體問題轉嚮玄學的抽象思辨。
經學方面，漢末鄭玄之經學已甚受推崇。然而在魏晉之世，王肅繼承父學而註經，其對經學的見解與鄭玄不同，遂有鄭、王兩派互相駁難。曹魏末年，司馬氏篡魏為晉。當時政治黑暗，知識份子之思想趨嚮反動、消沉而無出路。傾嚮曹氏者多是失勢士子，采取清談方式批評政治，主張自然。傾嚮司馬氏者，則主張維持名教，使儒傢作風漸起分化。因王肅為晉武帝外孫，遂被立為官學，一時黜鄭申王，使王學成為宗主。
《竹林七賢與榮啓期》，南朝大墓磚畫。由上至下，左至右分別為春秋隱士榮啓期及竹林七賢阮鹹、劉伶、嚮秀、嵇康、阮籍、山濤、王戎。
魏晉時期最突出的思想為玄學。其基本教義為《老子》、《莊子》和《周易》，合稱三玄。玄學家好談玄理，不談俗事，稱為清談，流行於魏晉時期。在240年－248年的醖釀期，以何晏和王弼為代表。玄學家認為一件事情需要理解其背後原理的“本”方能瞭解平常所見的表象“末”，進而提倡“以本統末”的理論。又視“本”為“道”，類比為沒有形體的“無”（原理、趨勢），視“末”為實際現象的“有”，並認為 “萬物皆産生於無”。之後到司馬炎篡魏建晉為止。以阮籍、嵇康等竹林七賢為代表，他們把焦點由思想理論轉移到人生問題上。當時政治黑暗，司馬氏壓抑士大夫，並以崇尚名教自飾。阮籍及嵇康等人遂主張儒教的禮法壓抑人性且虛偽，強調人性的解放與自然真誠。他們帶頭實現這個理論，形成一股解放個性的風氣。到了西晉之後，清談之風蔓延到政治舞臺上，握有大權的達官顯要也大談玄理，呈現一批在世又欲出世的權貴。斐頠對“自然”提出修正，主張“崇有論”，以矯“虛誕之弊”。郭象進一步證明“名教”即是“自然”，玄學發展至此已臻終結。
文學
三國文學中以曹魏文學最盛，分為前期的建安文學及後期正始文學，其中建安文學反對靡弱詩風，被後人稱為“建安風骨”或“漢魏風骨”。這是因為自曹操等人熱愛文學，各地文士紛紛吸附。建安文學代表人物為“三曹”及“建安七子”。其他的文學家還有邯鄲淳、蔡琰、繁欽、路粹、丁儀、楊修、荀緯等。曹操具有沉雄豪邁的氣概，古樸蒼涼的風格，著有〈短歌行〉、〈步出夏門行〉、〈讓縣自明本志令〉等文。曹丕及曹植才華洋溢，曹丕著有文學評論《典論》，導致文學開始自覺發展。曹植具浪漫氣質，著有〈洛神賦〉等文。建安七子與蔡琰、楊修等人關心現實，面嚮人生。他們的作品反映了漢末以來的社會變故和人民所遭受的苦難，例如蔡琰的〈鬍笳十八拍〉。
正始文學時期，由於當時政治形勢受司馬氏操控，文人備受壓抑，難以直接面對現實。當代的作傢有竹林七賢及何晏、夏侯玄、王弼等“正始名士”。正始作傢大都通老莊，好玄學，對於社會現實，不如建安作傢那樣執着，持比較衝淡的態度。嵇康的散文和阮籍的〈詠懷詩〉尚繼承“建安風骨”，敢於面對司馬氏政權，其文學都有鮮明的特色。《文心雕竜》提到“正始明道，詩雜仙心。何晏之徒，率多浮淺。惟嵇志清峻，阮旨遙深，故能標焉。”說明了阮籍和嵇康皆為正始文學的代表詩人。
孫吳作傢有張紘、薛綜、華核、韋昭等。張紘為孫權長史，與建安七子中的孔融、陳琳等友善。薛綜為江東名儒，居孫權太子師傅之位。華核則是孫吳末年作傢。蜀漢作傢有諸葛亮、郤正、秦宓、陳壽等。諸葛亮作為一代政治傢，他的作品有〈出師表〉等。其文彩雖不如他人豔麗，然而內容淺易，情意真切，感人肺腑，表露出他北伐的决心。秦宓所寫的五言詩〈遠遊〉，是蜀漢流傳下來唯一可靠的詩篇。蜀中亦多有學者為書作註的人，如：許慈、孟光、尹默、李撰等，蜀漢後期有譙周、郤正都醉心於文學，譙周更寫下了《仇國論》討論過度徵戰的缺點，及郤正以依照先代的儒士，藉文表達意見的〈釋譏〉。 東漢末年亦有研究纖圖、術數的學者，如：任安、周舒，之後出現了周群、杜瓊等人。
三國時期有名的史學家有王瀋、魚豢、韋昭及陳壽。王瀋的《魏書》被史學家劉知幾評為“其書多為時諱，殊非實錄”，這跟他親附司馬氏勢力，打壓魏帝曹髦有關，故該書的參考價值也相對較低。韋昭善寫史，著有〈吳鼓吹麯十二麯〉，內容為整部孫吳發展史，與繆襲的〈魏鼓吹麯十二麯〉南北相對。他又著有《吳書》55捲等。陳壽編寫的《三國志》為“前四史”之一。他參考《吳書》及魚豢撰寫的《魏略》等資料，采三國並述的方式，創新紀傳體史書的寫作模式。雖仍有不足之處，但實是研究三國歷史不可或缺的史籍之一。
宗教
本時期為佛教與道教的發展時期。由於天災人禍不斷，人民紛紛尋求宗教慰藉心靈，使得能夠逐漸發展。南中諸夷族的原始宗教，具有很濃厚的巫風。其性質是神話崇拜，具有多神、崇拜自然的特點。在西南地區有長遠的歷史，形成早期的原始宗教。
東漢民間流行黃老之學，張角建立的太平道和張道陵建立的五鬥米道，都是道教的雛型，到西晉時則稱為天師道。張角的太平道，在道術方面較重“守一”。以《太平經》為主要經典，又稱《太平青領書》。內容龐雜，“其言以陰陽五行為傢，而多巫覡雜語”。其社會思想既有維護統治階級利益的部分，也有呼籲公平、同情貧苦人民的部分。張角擁有廣大教衆後，於東漢末期率其弟張梁、張寶與部屬張曼成發起“黃巾之亂 ”，最後被東漢朝廷擊敗而漸漸式微。張道陵於漢順帝時入四川鶴鳴山，造作符書，創建五鬥米道。該教可能是黃老之學與當地宗教的融合，符文大多源至巴蜀巫術。五鬥米道與太平道教理教義基本相同，事奉黃老之學。張魯使教內“祭酒”誦習《老子五千文》，《道德經》成為主要經典之一。《老子想爾註》反映早期道教對《老子五千文》的解釋。經其子張衡（道教）、其孫張魯的傳播，流行於四川與漢中一帶。張魯投降曹操後，五鬥米道由巴、漢流傳到江南一帶。
佛教早在東漢初期即傳入中國，但當時儒學興盛，發展不大，至三國後方有發展。當時大乘佛教受貴霜帝國影響而傳播四周。西域受其影響，於闐、龜茲等地佛教興盛。之後又有天竺曇柯迦羅、安息曇諦和康居康僧鎧等僧侶到洛陽翻譯經典，將大乘佛教傳至中國。曇柯迦羅推廣戒律，這是中國僧侶有戒律受戒之始，後世以其為律宗的始祖。曇諦所譯的《曇無德（法藏）羯磨》受朱士行等人戒守，一般以此為中國僧侶出傢之始。由於當時經文翻譯未善，朱士行為求原經研讀，於260年自雍州出發至於闐，成為首位西行求法的中國僧侶。他寫得《大品般若》的梵本，後由弟子於282 年送回洛陽，最後由竺叔蘭譯成《放光般若經》。發展方面，在東漢末期笮融曾於江東大興佛寺。三國時期的佛教重鎮，北方以洛陽為主，南方則為建業。曹魏魏明帝大興佛寺，曹植也喜讀佛經，並創作梵唄。孫吳方面，當支謙、康僧會先後入吳，受孫權推崇並支持發展。孫皓稱帝時，本要毀壞佛寺，因康僧會說法感化，終而放棄。在蜀漢，佛教不是很興盛，規模不大。
藝術
三國在藝術方面，孫吳有很多擅長各種藝術的名士，時人稱為吳國八絶。有吳範、劉惇、趙達、嚴武、皇象、曹不興、宋壽和鄭嫗等人。例如嚴武擅下圍棋，同輩中無人能勝，有“棋聖”之稱。至於曹不興則擅繪畫、皇象則擅書法。
東漢末期動亂不堪，許多畫作被破壞或遺失，造成損失。佛教的發展，開始出現以佛教為題材的繪畫。三國時期的繪畫，因政治動蕩、社會混亂而沒有取得更大的成就。三國之前，繪畫主要屬於“百工之苑”的技術性職業，尚未藝術化，在本時期開始出現現實題材的內容，亦是由禮教宣傳過祖”，作品有《維摩詰圖》、《釋迦牟尼說法圖》等等。他曾把五十尺絹連在一起，畫一人像，心明手快，渡到宗教宣傳的時期。畫傢也由黃河流域的中原地區轉移到長江流域。當時有名的畫傢有曹不興、吳王趙夫人，其他擅長繪畫的有桓範、楊修、魏帝曹髦、諸葛瞻等人。孫吳曹不興，擅長寫生與繪佛畫，被譽為“佛畫之運筆而成。其作品富有立體感，世人有“曹衣出水”之稱，號“曹傢樣”。孫吳吳王趙夫人，吳丞相趙遠之妹，善於書法山水繪畫，時人譽為“針絶”。她為孫權繪各國山川地形圖，實開山水畫之首。漢末楊修相傳有《西京圖》等畫。曹魏桓範擅長丹青，魏帝曹髦繪畫人物史實。蜀漢諸葛瞻亦工書畫。
書法藝術興起於東漢末期。從三國到西晉，隸書仍是官方通行的書體，當時的碑刻大都用隸書寫成。曹魏碑文書體方正、氣度莊嚴，少有生趣。孫吳的著名碑刻有《天發神讖碑》、《禪國山碑》、《𠔌朗碑》等。其中《天發神讖碑》以圓馭方，勢險局寬，氣勢雄偉奇恣。本時期主要的書法傢有張芝、張昶、韋誕、鐘繇及皇象等人。張芝擅章草，並創新出今草。出名的作品有《冠軍帖》、《今欲歸帖》等。張昶為張芝季弟，擅長章草與隸書。韋誕總結書法經驗，著有《筆經》。其中“夫工欲善其事，必先利其器。”，正是他的名言。鐘繇《宣示表》、《薦季直表》等作品為楷書經典之作。皇象擅小篆、隸書，尤精章草。流傳作品有《急就章》、《文武將隊帖》及《天發神讖碑》等。
科技
馬鈞擅長機械應用，提升生産量，製作出水轉百戲和失傳的指南車，榮獲“天下之名巧”的美譽。他改良漢代的織綾機，使織出花紋具立體感，能與蜀錦相媲美。改良漢末畢嵐的竜骨車，發明出竜骨水車來灌溉較高位的農田。現在部份梯田仍在使用。他還將發石車改造成輪轉式發石車，提升拋擊量與速度。
諸葛亮為了方便在山地棧道運輸，發明“木牛流馬”。其構造歷代文獻有異，學者一般認定為獨輪車及四輪車，目前未有確實答案。他發明可以連續發射十箭的連弩，又稱“元戎”。另外，據說源自諸葛亮設計，用於傳遞信號的孔明燈，被公認為熱氣球的始祖；據《事物紀原》載，諸葛亮也最早製造出長槍的原形，長槍最後漸漸取代了長矛。
劉徽為數學家，他自幼對數學有興趣，學習中國古代數學的重典《九章算術》。年長後於曹魏景元四年（263年）著有《九章算術註》，藉由自己的註解，使其容易瞭解。之後劉徽又著作《九章算術註》的第十捲，即《重差》（後稱《海島算經》），這使中國測量學達到登峰造極的地步。
醫學方面，有名的有華佗、張仲景和皇甫謐。華佗醫術精湛，擅長外科手術。他與董奉、張仲景被史書稱為“建安三神醫”。不過關於他醫術傳奇的部份，史學家陳寅恪認為應該源自印度的佛教傳說。然而，他可能是最早使用麻醉劑“麻沸散”進行外科手術的醫者。張仲景鑒於當代動亂頻繁，疫病流行，致力研究疾病，參考各傢書籍寫出《傷寒雜病論》。該書集兩漢醫經、經方二派的大成，是中醫史上第一部理法方藥具備的經典，喻嘉言稱此書：“為衆方之宗、群方之祖”。後世奉其為“醫聖”。皇甫謐自幼傢頻，學習廢寢忘食，淡於名利而不願任官。他對針灸深入研究，將晉代之前各種經脈理論與針灸方法整理成《針灸甲乙經》，該書成為後世針灸學的範典。他還著有《寒食散論》，魏晉之後服食寒食散逐漸的流行起來。
關於其他技術，天文學方面，有先後擔任孫吳與西晉太史令的陳卓。他收集各派資訊，完善中國星官體製，並繪製星圖，為後世所沿用。裴秀的“製圖六體”在中國地圖史上占有重要的位置。蒲元擅長鍛鏈鐵器，他在斜𠔌（今陝西省眉縣西南）為諸葛亮製刀。其刀能劈開裝滿鐵珠的竹筒，譽為神刀。由於孫吳位於江南地區，水路發達，造船技術發達。其戰船有的上下五層，有的還能容納士兵三千人。蜀漢盛産井????，利用當地的天然氣來煮????，提升了産能。
三國兵製
魏的中央軍，分中軍和外軍。中、外軍的來歷，何茲全《魏晉的中軍》一文作了明確的闡述：“‘中軍’是對‘外軍’而來的，中外軍的區別形成於漢建安時代（196至220年），到魏黃初年間（220至226年）都督製成立，中外軍的區分及中外軍的名稱也就正式成立。建安以前，曹操集團不過是當時割據局面下的群雄之一。曹操迎獻帝都許，挾天子以令諸侯，尤其是在官渡之戰，打敗袁紹，取得冀、並、青諸州以後，他的統治區纔漸具國傢的規模。這時局面大了，再不能象過去一樣，帶領一支軍隊（雖不是全部也是大部）到處徵戰，因之便産生了留屯的辦法。平定一個地方，即留一部分軍隊在那裏駐防，並由一人任統帥，統攝轄區內諸軍。這種留屯製，實即魏晉以下盛行的軍事上分區的都督諸軍製的濫觴。這種情形，發生於曹操打敗袁紹占有冀、並諸州之後，到赤壁戰後，三國鼎峙的局面形成，便漸漸固定為一種制度，而且發展為後來的都督製。國傢的軍隊既在事實上分了內外，內外的名稱自然也跟着形成，留屯在外的將軍及都督所領的兵，就稱為外軍；中央直轄的軍隊，就稱為中軍。”
魏的中軍略等於漢代的南北軍，擔負着宿衛皇宮、拱衛京師的任務，《歷代兵製》認為“魏製略如東漢，南北軍如故”，依然把魏的中軍稱為南北軍。不過由於漢末三國戰事頻仍，中軍常常四出徵伐，與漢代北軍相比，魏中軍的作戰任務重得多。
《歷代兵製》敘述了魏中軍的發展：“初，曹公自置武衛營於相府，以領軍主之。及文帝增置中營，於是有武衛、中壘二營，以領軍將軍並五校統之。”武衛營是曹魏集團最親近的宿衛禁兵，其設置時間，《補三國兵志》說在建安十三年（公元208年）。那時曹操剛做相國，便在相府自置武衛營。當時漢帝的禁兵為數已不多，且在曹操控製之下，武衛營一成立，相府更是威重漢宮。武衛營的統帥最初是許褚，官職為武衛中郎將，後遷武衛將軍。曹魏作武衛將軍的，都是皇帝很親近的人。魏文帝置中壘、中堅二營，歸中領軍統帥，魏明帝又置驍騎，遊擊二營。《歷代兵製》衹提到武衛、中壘二營，有所疏漏。“武衛、中壘二營，以領軍將軍並五校統之”，也是不確的。事實上，曹魏先後置武衛、中壘、中堅、驍騎、遊擊等新五營，歸中領軍統帥；東漢以來北軍的屯騎、步兵、射聲、越騎、長水五營，曹魏時期依然存在，但兵員已少的可憐，五校地位已不如武衛將軍等，已無可能去統帥武衛、中壘等新營。
關於魏中軍的組織係統，《歷代兵製》說：“有中、左、右、前軍各一師，又有中護、中領軍、領、護軍將軍各一人。其他雜號無常數。”陳傅良認為，漢的南北軍到曹魏時期演變為中、左、右、前軍了。其實，衹有中軍相當於漢的南北軍，所謂左、右、前軍等，顯然與中軍相對，可能是對留屯在不同地方的外軍的稱呼。《三國志》、《資治通鑒》常有“東兵”、“東軍”一類提法，都是指留屯東方的外軍，左、右、前軍等也是這類提法。中軍的統帥，陳傅良認為有“中護、中領軍、領、護軍將軍各一人”。歷來談曹魏兵製者，多象他一樣，以為魏中軍同時存在中護軍、中領軍與領軍、護軍這樣一批統帥。其實領軍與護軍和中領軍與中護軍是不同時期的職官。《玉海》捲一三七：“魏武為相，以韓浩為護軍，史渙為領軍，非漢官也。建安十二年，改護軍為中護軍，領軍為中領軍。”這段話與史實略有出入，但指出中護軍、中領軍的前身就是護軍、領軍，無疑是正確的。改領軍、護軍為中領軍、中護軍，是由於當時中央軍在事實上已分成中軍與外軍，所以要在中軍統帥領軍、護軍前冠以中字。由於領、護軍改名中領、中護軍後還有人沿襲舊稱，載之史書，故後人往往認為領、護軍與中領、中護軍並存。對於中領軍或中護軍中資歷厚重者，可進稱為領軍將軍或護軍將軍，但中軍也不可能同時既有領軍將軍、護軍將軍，又有中領軍、中護軍。中領軍是中軍諸營的統帥，他親領中領營，並兼領中軍諸營；中護軍在中軍的地位僅次於中領軍，他負責武官的選用，並親領中護營。
留屯各地的外軍，開始編製很不一致，統帥往往臨時由中央委派和更換。到魏文帝時，情況發生了變化。《歷代兵製》：“黃初三年，特置都督諸州軍事，尋加四徵四鎮將軍之號，又置大將軍都督中外諸軍，位太尉上。”曹魏的都督諸州軍事，是代表中央分駐各地的軍事長官，所領是不同於州郡兵的中央軍隊。所謂四徵四鎮，是指徵東將軍、徵南將軍、徵西將軍、徵北將軍與鎮東將軍、鎮南將軍、鎮西將軍、鎮北將軍等稱號，此外還有所謂四安四平將軍的稱號，這些都不是固定軍職，而是臨時贈封的稱號。從這些稱號也可以知道，那些都督諸州軍事的將軍，是代表中央去行徵伐鎮壓之權。中外諸軍即中軍與外軍，“置大將軍都督中外諸軍”，則是以大將軍統帥全國中央軍，大將軍成為曹魏最高軍事統帥。曹魏政權是取代東漢王朝而建立的，開始仍以太尉為最高軍政長官，置大將軍後，太尉最重要的權力被分割，所以陳傅良說大將軍“位太尉上”。
綜上所述，曹魏中央軍的係統是：
|——中軍-領軍、護軍——諸營將校
中央軍-大將軍——|
|——外軍-都督諸州軍事
除了中軍與外軍，曹魏政權還有作為地方兵的州郡兵。東漢光武帝罷兵募士，郡國兵力十分薄弱。到東漢末年，一些州郡守割據稱雄，兵力轉強，多數州郡的軍隊則逐一消滅或兼併。曹操統一北方，大大小小的割據武裝或被消滅，或被收編，北方各州郡往往衹有留屯的中央軍，而沒有地方武裝了。當時丞相主簿司馬朗建議令州郡都建立地方武裝，以“外備四夷，內威不軌”。《歷代兵製》：“自納司馬朗之言，復令州郡典兵，然未置尉，蓋太守或刺史兼帥。”州郡兵以守備本州郡為職，必要時也應調出徵。州郡兵地位比中軍、外軍低，“州郡都督不與中外軍同......苟在中軍之例，雖下功必侯；如在州郡，雖功高不封”（《晉書.段灼傳》），但地方州郡長官的權力卻藉此大大膨脹起來。所以《歷代兵製》認為，曹魏政權的“兵權外聚於州牧，內歸於大將軍及太尉”。因此後來有人上疏魏明帝，要求解除緣邊州郡刺史、太守的領兵權，另外派遣大將去鎮守，以免刺史、太守領了兵則“專心軍功，不勤民事”，而不能“獨修務本之業”（《三國志.魏志.杜恕傳》）。
曹魏兵製，還有屯田兵值得一提，但陳傅良對此又疏漏了。曹魏的屯田分民屯和兵屯兩種，是漢代官田出租辦法及邊郡屯田的推廣。民屯的管理方式是：由大司農掌管全國的民屯，典農中郎將負責一州郡的民屯，典農都尉負責一縣級單位的民屯，屯司馬負責一生産單位——一屯。每一屯有屯田客五十人。民屯的任務是種植稻、粟、桑、麻，百分之五十至六十的收穫上繳政府。屯田客不服兵役，但實行軍法部勒式管理，應該納入兵製研究的範圍。建安初年開始的屯田，本是為了束縛流民於土地和為政府提供大量租入以充軍需；到魏末晉初，統治者為了世傢大族的利益，經常分割屯田，瓜分屯田客，屯田制度遭到毀滅性破壞。兵屯的開始晚於民屯，一般是保持原有的軍事編製，設立在與吳蜀兩國對峙的邊境，讓士兵且佃且守。東吳也有與曹魏大體相似的兵.
蜀漢兵製大致和魏相同，但又有其特點。蜀的中央軍，《歷代兵製》說：“蜀置五軍。其左、右將軍、督、護一人，其中師、監、護、典、參軍各一人，其前師、將軍、監、護、督軍各一人，其後督、將軍、兼一人。其將校略如漢。”五軍即前、後、左、右、中軍。中軍與曹魏一樣同時又是宿衛部隊；前、後、左、右四軍略等於曹魏的外軍。蜀漢中央軍置軍師將軍一至二人，為全國最高軍事統帥。五軍的組織係統不完全一樣，中軍有護軍、監軍、軍師、都護、領軍、典軍各一人；前、後軍有護軍、監軍、軍師、領軍、典軍各一人；左、右軍有護軍、監軍、都護各一人。據《三國志. 蜀志.關張馬黃趙傳》，前、後、左、右軍的統帥分別是前將軍、後將軍、左將軍、右將軍，衹有中軍統帥是護軍；而據王平、劉敏、姜維等傳，前、後、左、右四軍又常以護軍或監軍為各自的統帥。因此，前將軍等官號，究竟是護軍的另稱還是進稱，或者是不同時候的職官，還有待進一步考查。
蜀的基層軍隊，有許多不同的稱號。《歷代兵製》：“兵有突將、無前、（上宗下貝）叟、青羌、散騎、武騎之別，蓋不全用蜀人也。”“劉璋時，三輔流人數萬，收以為兵，號東州兵。”這裏所舉的尚不完全，據王欣夫《補三國兵志》統計，蜀有以下稱號的基層軍隊：麯長，漢軍本有部和麯的編製，蜀有麯長，則在部分軍隊尚有麯的編製。屯將，蜀有屯將，則有屯的編製。突將，衝鋒隊的將領，則蜀軍往往有專門的前鋒隊。無前、無當，二者可能同為一支精勇的隊伍。飛軍，以羌族的一支——青羌為主，分為五部。虎步，精勇的步兵隊伍。虎騎，精勇的騎兵隊伍，此外還有散騎、武騎等騎兵隊。白（目毛），由以白羽毛為飾的少數民族組成。（上宗下貝）叟，由（上宗下貝）人（湘、川一帶的少數民族）組成。此外還有夷兵，由荊州一帶少數民族組成。從這些稱號可以看出，蜀政權不僅讓蜀中漢人當兵，而且大量以外族為兵，組成飛軍、青羌、白（目毛）、（上宗下貝）叟、夷兵等外族軍隊。從東州兵的情況還可看出，蜀漢還把外來流民組建成軍隊。
東吳兵製比較雜亂，大體也與魏無異。其軍隊特點，如《歷代兵製》所說：“吳多舟師，營校略異於漢。”東吳立國江南，北有長江天險，東南有東海、南海，內地多湖泊水澤，多水域的自然條件，尤其是豐富的物産和發達的經濟，决定其水軍強於魏、蜀，以致數次以舟師挫敗來進攻的曹魏大軍。東吳的般衹體積大、數量多，並且有艨艟、鬥艦、樓船、飛雲、蓋海、赤竜、馳馬、長安、大舶、大（舟扁）、青竜戰艦、晨鳧等衆多名號。根據《吳書》的記載，當時能載馬八十匹的還算小船（《三國志.吳志.孫權傳》嘉禾二年註引）。又根據《晉陽秋》，西晉滅吳時，接收其船衹五千餘艘（《三國志.吳志.孫皓傳》註引），其中包括運輸船和戰船，運輸船中，相當大一部分屬於水軍作運輸軍需用。這樣，我們雖不能得知東吳水軍船衹的具體數字，但其規模之大則是可以想見的。當時東吳水軍舟師不僅時刻巡守長江天險，而且遊弋於遼闊海域。東吳水軍統帥為水軍都督。
東吳的中央軍與曹魏、蜀漢相同，有前、後、左、右、中五軍，軍中將領亦有護軍、領軍、典軍、軍司馬等。一旦進行戰爭置大都督總領五軍，各軍置部督等。
東吳軍隊大部分由山居的越人組成，以山越為兵，僅見於記載的已不下十餘萬。西晉滅東吳時，接收其軍隊二十三萬。東吳軍隊有許多不同名號。《歷代兵製》：“兵有解煩、敢死兩部，車下虎士、丹陽青巾、交州義士及健兒、武射之名非一，調度亦最無法。”這裏列舉的也很不完全。據王欣夫《補三國兵志》統計，東吳軍隊有下列名號：羽林，是宮廷禁衛部隊。虎騎，拱衛京城的騎兵部隊。敢死、解煩、無難、馬閑，都是精勇的衝鋒隊，多分左右兩部，各以左部督和右部督領兵。五營、五校，各有五營兵，五營有五營督領兵，五校有五校督領兵。升城、繞帳、外部、營下、帳下，大約都是屯駐在京城以外的隊伍，分屬前、後、左、右四軍。還有車下虎士、丹陽青巾、交州義士、健兒、勇敢、虎射吏等名號的地方兵。從義士、健兒等名號推測，這些地方隊伍可能大多為東吳豪族將帥厚養的子弟兵。《三國志.吳志.甘寧傳》：“能厚養健兒，健兒亦樂為用命”。可見這些隊伍與其世襲將領的關係非常特殊。
三國時期的經濟
魏國經濟
曹操迎獻帝於許昌後，以「夫定國之術，在於強兵足食」為方針，在許昌附近實行屯田。結果「募民屯田許下，得𠔌百萬斛」。因此，操設置田官於各州郡內，招募流民屯田，把屯田製加以推廣，以改東漢末年軍閥混戰所做成的「白骨露於野，千裏無雞鳴」的境況。正因屯田製之成功，地方變成「農官兵田，雞犬之聲，阡陌相屬」正因采取屯田措施，使北方的社會轉嚮穩定，終達至「徵伐四方，無運糧之勞，遂兼滅群賊，剋平天下」。
蜀國經濟
蜀自古以來已有天府之國的美名，漢高祖能得天下亦靠此地物質豐厚為根本。 東漢末年，劉焉父子先後擔任益州牧，用以寬製寬之政策以治蜀，逐引緻豪強壟斷土地及山澤資源，因而減低稅收。自劉備占領益州後，諸葛亮及法正一改以往弊政，打擊豪強，並曾采用閉關息民，務農殖𠔌。又在都江堰設堰官，管理農田水利工程，並推行屯田，以恢復和發展農業生産。此外。亮及法正對冶鐵、煮????、織綿等重要手工業，實行公營，並設立專職官員加強管理。以上一連串措施，使國傢稅收大大增加，奠定了三足鼎立的條件。後來關羽失荊州，備討伐吳敗亡，使蜀面臨崩潰邊沿，故亮在經濟方面擴大手工業官營範圍，提高蜀綿生産量，以助加快恢復國力之步伐。
吳國經濟
東漢末年，群雄逐鹿，中原地方連年徵戰，地方殘破，北方人民攜傢渡江以避難。北方難民不乏富商大賈，他們由北方走難到江南同時，帶備了生産技術與文化，為當時貧睏的江南帶來新血。原本吳農耕技術十分落後，尚未懂得牛耕。及後生産技術註入，農業生産技術逐漸提高，人口亦因此漸漸增加，一改以往地廣人稀的境況。孫氏三代：孫堅、孫策、孫權之統治領地漸大，軍隊亦因此變得龐大，故此糧草軍需耗費成為國傢支出中的一大部分，為減輕負擔，逐實行屯田製，並設置典農校尉和典農都尉。屯田製有分兵屯及民屯。兵屯下之耕者為佃兵，民屯下之耕者為屯田客。吳位於長江流域以下，故亦註意興修水利，以利用水力資源和作軍事防備。
東漢十三部州（三國行政區域）
司隸校尉部：治所 河南（今洛陽市東）轄區，今陝中部，秦西南部及豫西部。稱為“司州”。
豫州：治所 譙（qiáo，皖亳縣）轄區，今豫南部、東部、皖北部、蘇西北角及山東西南角。
兗州：治所 昌邑（今魯金鄉縣西北）轄區，今山東西南部，豫東部和蘇西北角。
徐州：治所 郯（tán，魯郯城縣西南）轄區，今魯東南部，蘇北部及皖東北角。
青州：治所 臨錙 轄區，今魯北部及冀東南西角。
涼州：治所 隴（甘清水縣北） 轄區，今甘東東部。
並州：治所 晉陽（太原市西）今陝北部，秦大部及內蒙之一部。
冀州：治所 鎬（hào）（冀柏鄉縣北）轄區，今冀西南部。
幽州：治所 薊（jì，北京城西南）。轄區 今冀北部，遼、吉各一部。
揚州：治所 歷陽（皖和縣，後遷壽春） 轄區 今蘇南部、皖中南部，浙、閩、贛三省。
荊州：治所 漢壽（湘常德市東） 轄區 今豫西南部，鄂、湘二省及黔、桂、粵三省邊緣。
益州：治所 雒(luò，川廣漢市，後綿竹，再成都) 轄區 今川、黔、滇三省大部，陝及鄂、甘各一隅。
交州：治所 廣信（桂梧州市）。
The Three Kingdoms period (simplified Chinese: 三国时代; traditional Chinese: 三國時代; pinyin: Sānguó shídài) is a period in the history of China, part of an era of disunity called the Six Dynasties following immediately the loss of de facto power of the Han Dynasty emperors. In a strict academic sense it refers to the period between the foundation of the Wei in 220 and the conquest of the Wu by the Jin Dynasty in 280. However, many Chinese historians and laymen extend the starting point of this period back to the uprising of the Yellow Turbans in 184.
The three kingdoms were Wei (魏), Shu (蜀), and Wu (吳). To help further distinguish these states from other historical Chinese states of the same name, historians add a relevant character: Wei is also known as Cao Wei (曹魏), Shu is also known as Shu Han (蜀漢), and Wu is also known as Dong Wu or Eastern Wu (東吳). The term Three Kingdoms itself is somewhat of a mistranslation, since each state was eventually headed not by kings, but by an emperor who claimed legitimate succession from the Han Dynasty. Although the translation Three Empires is more contextually accurate, the term Three Kingdoms has become standard among sinologists.
The earlier, "unofficial" part of the period, from 184 to 220, was marked by chaotic infighting between warlords in various parts of China. The middle part of the period, from 220 and 263, was marked by a more militarily stable arrangement between three rival states, Cao Wei, Shu Han, and Eastern Wu. The later part of this period was marked by the collapse of the tripartite situation: first the destruction of Shu by Wei (263), then the overthrow of Wei by the Jin Dynasty (265), and the destruction of Wu by Jin (280).
Although relatively short, this historical period has been greatly romanticised in the cultures of China, Japan, Korea, and Vietnam. It has been celebrated and popularised in operas, folk stories, novels and in more recent times, films, television series, and video games. The best known of these is undoubtedly the Romance of the Three Kingdoms, a novel dealing with the period that draws heavily on history. The authoritative historical record of the era is Chen Shou's Sanguo Zhi, along with Pei Songzhi's later annotations of the text.
The Three Kingdoms period was one of the bloodiest in Chinese history. A population census during the late Eastern Han Dynasty reported a population of approximately 50 million, while a population census during the early Western Jin Dynasty (after Jin re-unified China) reported a population of approximately 16 million. However, the Jin dynasty's census was far less complete than the Han census, so these figures are in question.
Technology advanced significantly during this period. Zhuge Liang invented the wooden ox, suggested to be an early form of the wheelbarrow, and improved on the repeating crossbow. A brilliant mechanical engineer known as Ma Jun, in Wei, is considered by many to be the equal of his predecessor Zhang Heng. He invented a hydraulic-powered, mechanical puppet theatre designed for Emperor Ming of Wei (Cao Rui), square-pallet chain pumps for irrigation of gardens in Luoyang, and the ingenious design of the South Pointing Chariot, a non-magnetic directional compass operated by differential gears.
Yellow Turban Rebellion
The power of the Eastern Han Dynasty went in to depression steadily declined after the reign of Emperor He of Han from a variety of political and economic problems. A series of Han emperors ascended the throne while still youths, and de facto Imperial power often rested with the young emperors' older relatives. Because these relatives occasionally were loath to give up their influence, emperors would, upon reaching maturity, be forced to rely on political alliances with senior officials and eunuchs to achieve control of the government. Political posturing and infighting between Imperial relatives and government eunuchs was a constant problem in Chinese government at the time. During the reigns of Emperors Huan and Ling, leading officials' dissatisfaction with the eunuchs' usurpations of power reached a peak, and many began to openly protest against them. The first and second protests met with failure, and the court eunuchs persuaded the Emperor to execute many of the protesting scholars. Some local rulers seized the opportunity to exert despotic control over their lands and citizens, since many feared to speak out in the oppressive political climate. Emperors Huan' and Ling's reigns were recorded as particularly dark periods of Han Dynasty rule. In addition to political oppression and mismanagement, China experienced a number of natural disasters during this period, and local rebellions sprung up throughout China.
In the second month of 184 AD, Zhang Jue, leader of the Dao of Supreme Harmony Daoist movement, along with his two brothers Zhang Liang and Zhang Bao, led the movement's followers in a rebellion against the government that was called the Yellow Turban Rebellion. Their movement quickly attracted followers and soon numbered several hundred thousands and received support from many parts of Han China. They had 36 bases throughout China, with large bases having 10,000 or more followers and minor bases having 6,000 to 7,000, similar to Han armies. Their motto was: "The Han Emperor's already dead, Lord Zhang Jue shall take his stead; the year-cycle is at its head, into fortune shall all be led!" (Chinese: 蒼天已死，黃天當立，歲在甲子，天下大吉) Emperor Ling of Han dispatched Generals Huangfu Song, Lu Zhi, and Zhu Jun to lead the Han armies against the Yellow Turbans, and decreed that local governments had to supply soldiers to assist in their efforts. It is at this point that the great epic Romance of the Three Kingdoms begins its narrative. The Yellow Turbans were ultimately defeated and its surviving followers dispersed throughout China, but due to the turbulent situation throughout the empire, many were able to survive as bandits in mountainous areas, thus continuing their ability to contribute to the turmoil of the era.
With the widespread increase in bandits across the Chinese nation, the Han army had no way to repel each and every raiding party. In 188, Emperor Ling accepted a memorial from Yizhou governor Liu Yan suggesting he grant direct administrative power over feudal provinces and direct command of regional military to local governors, as well promoting them in rank and filling such positions with members of the Liu family or court officials. This move made provinces (zhou) official administrative units, and although they had power to combat rebellions, the later intra-government chaos allowed these local governors to easily rule independently of the central government. Soon after this move, Liu Yan severed all of his region's (modern Sichuan) ties to the Han court, and several other areas followed suit.
Dong Zhuo in power
That same year, Emperor Ling died, and another struggle began between the court eunuchs for control of the Imperial family . Court eunuch Jian Shuo planned to kill General He Jin, a relative of the royal family, and to replace the Crown Prince Liu Bian with his younger brother Liu Xie, the Prince of Chenliu (in modern Kaifeng), though his plan was unsuccessful. Liu Bian took the Han throne as Emperor Shao of Han, and General He Jin plotted with warlord Yuan Shao to assassinate the Ten Attendants, a clique of ten eunuchs led by Zhang Rang who controlled much of the imperial court. He Jin also ordered Dong Zhuo, the frontier general in Liangzhou, and Ding Yuan, Inspector of Bingzhou (the area now between Baoding and Taiyuan), to bring troops to the capital to reinforce his position of authority. The eunuchs learned of General He's plot, and had him assassinated before Dong Zhuo ever reached the capital, Luoyang. When Yuan Shao's troops reached the capital they stormed the palace complex, killing the Ten Attendants and two thousand of those loyal to them. Though this move effectively ended the century-long feud between the eunuchs and the Imperial family, it ushered in the era of warlords and martial law that became the Three Kingdoms Era.
This event prompted the invitation of Dong Zhuo to enter Luoyang from the northwest boundary of China. At the time China faced the powerful barbarians of Qiang tribe to the northwest, and thus Dong Zhuo controlled a large army with elite training. When he brought the army to Luoyang, he was able to easily overpower the existing armies of both sides and took control of the imperial court, ushering in a period of civil war across China.
Dong Zhuo then manipulated the succession so that the future Emperor Xian could take the throne in lieu of his elder half-brother. Dong Zhuo, while ambitious, genuinely wished for a more capable emperor. On his way to Luoyang, he encountered a small band of soldiers protecting the two sons of Emperor Ling fleeing the war zone. In the encounter Dong Zhuo acted arrogantly and threateningly, causing the elder half-brother to be paralyzed with fear; the younger brother, the future Emperor Xian, responded calmly with authority and commanded Dong Zhuo to protect the royal family with his army to return to the Imperial Court.
While Dong Zhuo originally wanted to re-establish the authority of Han Empire and manage all the political conflict properly, his political capability proved to be much worse than his military leadership. His behaviour grew more and more violent and authoritarian, executing or sending into exile all that opposed him, and showed less and less respect to the Emperor. He ignored all royal etiquette and frequently carried open weapons into the imperial court. In 190 a coalition led by Yuan Shao was formed between nearly all the provincial authorities in the eastern provinces of the empire against Dong Zhuo. The mounting pressure from repeated defeat on the southern frontline against the Sun Jian forces drove the Han Emperor and later Dong Zhuo himself west to Chang'an in May 191.
Dong Zhuo once again demonstrated his political shortcomings by forcing millions of residents of Luoyang to migrate to Chang'an. He then set fire to Luoyang, preventing occupation by his enemies and destroying the biggest city in China at that time. In addition, he ordered his army to slaughter a whole village of civilians. The soldiers beheaded the civilians and carried their heads into Chang'an to show off as war trophies, pretending to have had a great victory against his enemies. A year later Dong Zhuo was killed in a coup d'etat by Wang Yun and Lü Bu.
Rise of Cao Cao
Sculpture of a foreign soldier, Three Kingdoms, 3rd century AD, China.
In 191, there was some talk among the coalition of appointing Liu Yu, an imperial relative, as emperor, and gradually its members began to fall out. Most of the warlords in the coalition, with a few exceptions, sought the increase of personal military power in the time of instability instead of seriously wishing to restore the Han Dynasty's authority. The Han empire was divided between a number of regional warlords. Yuan Shao occupied the northern area of Ye and extended his power, by taking over his superior Han Fu with trickery and intimidation, north of the Yellow River against Gongsun Zan, who held the northern frontier. Cáo Cāo, directly to Yuan's south, was engaged in a struggle against Yuan Shu and Liu Biao, who occupied respectively the Huai River basin and Middle Yangzi regions. Further south the young warlord Sun Ce, taking over after the untimely death of Sun Jian, was establishing his rule in the Lower Yangzi, albeit as a subordinate of Yuan Shu. In the west, Liu Zhang held Yizhou province while Hanzhong and the northwest were controlled by a motley collection of smaller warlords such as Ma Teng of Xiliang, the original post of Dong Zhuo.
Dong Zhuo, confident in his success, was slain by his own adopted son, Lü Bu and his father-in-law Wang Yun. Lü Bu, in turn, was attacked by Dong Zhuo's supporters: Li Jue, Guo Si, Zhang Ji and Fan Chou. Wang Yun and his whole family were executed. Lu fled to Zhang Yang, a northern warlord, and remained with him for a time before briefly joining Yuan Shao, but it was clear that Lü Bu was far too independent to serve another.
In August 195, Emperor Xian fled the tyranny of Li Jue at Chang'an and made a year long hazardous journey east in search of supporters. By 196, when he was received by Cao Cao, most of the smaller contenders for power had either been absorbed by larger ones or destroyed. This was an extremely important move for Cao Cao following the suggestion from his primary advisor, Xun Yu, commenting that by supporting the authentic Emperor, Cao Cao would have the formal legal authority to control the other warlords and force them to comply in order to restore the Han dynasty.
Cao Cao, whose zone of control was the precursor to the Kingdom of Wei, had raised an army in the winter of 189. In several strategic movements and battles, he controlled the Dui province and defeated several factions of the Yellow Turban rebels. This earned him the aid of other local militaries controlled by Zhang Miao and Chen Gong, who joined his cause to create his first sizable army. He continued the effort and absorbed approximately 300,000 Yellow Turbans into his army as well as a number of clan-based military groups from the eastern side of Qing province. In 196 he established an imperial court at Xuchang and developed military agricultural colonies (tuntian) to support his army. Although the system imposed a heavy tax on hired civilian farmers (40% to 60% of agricultural production), the farmers were more than pleased to be able to work with relative stability and professional military protection in a time of chaos. This was later said to be his second important policy for success.
In 194, Cao Cao went to war with Tao Qian of Xuzhou, whose officers had executed his whole family. Tao Qian received the support of Liu Bei and Gongsun Zan, but even then it seemed as if Cao Cao's superior forces would overrun Xuzhou entirely. However, Cao Cao received word that Lü Bu had seized Yan province in Cao Cao's absence, and accordingly he retreated, putting a halt to hostilities with Tao Qian for the time being. Tao Qian died that same year, leaving his province to Liu Bei. A year later, in 195, Cao Cao managed to drive Lü Bu out of Yan. Lu Bu fled to Xuzhou and was received by Liu Bei, and an uneasy alliance began between the two.
In the south, Sun Ce, then an independent general under the service of Yuan Shu, defeated the warlords of Yangzhou, including Liu Yao, Wang Lang, and Yan Baihu. The speed with which Sun Ce accomplished his conquests led to his nickname, "Little Conqueror" (小霸王), a reference to the late Xiang Yu. In 197, Yuan Shu, who was at odds with Cao Cao, Yuan Shao, and Liu Bei, felt assured of victory with his subordinate's conquests, and thus declared himself emperor of the Cheng Dynasty. The move, however, was a strategic blunder, as it drew the ire of many warlords across the land, including Yuan Shu's own subordinate Sun Ce, who had advised Yuan Shu not to make such a move. Cao Cao issued orders to Sun Ce to attack Yuan Shu. Sun Ce complied, but first convinced Cao Cao to form a coalition against Yuan Shu, of which Liu Bei and Lü Bu were members. Attacked on all sides, Yuan Shu was defeated and fled into hiding.
Afterwards, Lü Bu betrayed Liu Bei and seized Xuzhou, forming an alliance with Yuan Shu's remnant forces. Liu Bei fled to Cao Cao, who accepted him. Soon, preparations were made for an attack on Lü Bu, and the combined forces of Cao Cao and Liu Bei besieged Xia Pi. Lü Bu's officers deserted him, Yuan Shu's forces never arrived as reinforcements, and he was bound by his own officers Song Xian and Wei Xu and executed along with many of his officers. Thus, the man known as the mightiest warrior in the land was no more.
In 200, Dong Cheng, an officer of the Imperial Court, received a secret edict from the Emperor to assassinate Cao Cao. He collaborated with Liu Bei on this effort, but Cao Cao soon found out about the plot and had Dong Cheng and his co-conspirators executed, with only Liu Bei surviving and fleeing to the Yuan Shao in the north.
After settling the nearby provinces, including a rebellion led by former Yellow Turbans, and internal affairs with the court, Cao Cao turned his attention north to Yuan Shao, who himself had eliminated his northern rival Gongsun Zan that same year. Yuan Shao, himself of higher nobility than Cao Cao, amassed a large army and camped along the northern bank of the Yellow river.
In 200, after winning a decisive battle against Liu Biao at Shaxian and putting down the rebellions of Xu Gong and others, Sun Ce was struck by an arrow and fatally wounded. On his deathbed, he named his younger brother, Sun Quan, as his heir.
Following months of planning, Cao Cao and Yuan Shao met in force at Guandu. Overcoming Yuan's superior numbers, Cao Cao decisively defeated him by setting fire to his supplies, and in doing so crippled the northern army. Liu Bei fled to Liu Biao of Jing province, and many of Yuan Shao's forces were destroyed. In 202, Cao Cao took advantage of Yuan Shao's death and the resulting division among his sons to advance north of the Yellow River. He captured Ye in 204 and occupied the provinces of Ji, Bing, Qing and You. By the end of 207, after a lightning campaign against the Wuhuan barbarians, Cao Cao had achieved undisputed dominance of the North China Plain.
Battle of Red Cliff
In 208, Cao Cao marched south with his army hoping to quickly unify the empire. Liu Biao's son Liu Cong surrendered the province of Jing and Cao was able to capture a sizable fleet at Jiangling. Sun Quan, the successor to Sun Ce in the Lower Yangzi, continued to resist, however. His advisor Lu Su secured an alliance with Liu Bei, himself a recent refugee from the north, and Sun Ce's sworn brother Zhou Yu was placed in command of Sun Quan's navy, along with a veteran officer of the Sun family, Cheng Pu. Their combined armies of 50,000 met Cao Cao's fleet and 200,000-strong force at Red Cliffs (Chinese: 赤壁 Chi Bi) that winter. After an initial skirmish, an attack beginning with a plan to set fire to Cao Cao's fleet was set in motion to lead to the decisive defeat of Cao Cao, forcing him to retreat in disarray back to the north. The allied victory at Red Cliffs ensured the survival of Liu Bei and Sun Quan, and provided the basis for the states of Shu and Wu.
After his return to the north, Cao Cao contented himself with absorbing the northwestern regions in 211 and consolidating his power. He progressively increased his titles and power, eventually becoming the Prince of Wei in 217, a title bestowed upon him by the puppet Han emperor that he controlled. Liu Bei, having defeated the weak Jing warlords Han Xuan, Jin Xuan, Zhao Fan, and Liu Du, entered Yi province and later in 214 displaced Liu Zhang as ruler, leaving his commander Guan Yu in charge of Jing province. Sun Quan, who had in the intervening years being engaged with defenses against Cao Cao in the southeast at Hefei, now turned his attention to Jing province and the Middle Yangzi. Tensions between the allies were increasingly visible. In 219, after Liu Bei successfully seized Hanzhong from Cao Cao and as Guan Yu was engaged in the siege of Fan, Sun Quan's commander-in-chief Lu Meng secretly seized Jing province, and his forces captured and slew Guan Yu.
Three Emperor
In the first month of 220, Cao Cao died and in the tenth month his son Cao Pi forced Emperor Xian to abdicate, thus ending the Han Dynasty. He named his state Wei and made himself emperor at Luoyang. In 221, Liu Bei named himself Emperor of Han, in a bid to restore the fallen Han dynasty. (His state is known to history as "Shu" or "Shu Han".) In the same year, Wei bestowed on Sun Quan the title of King of Wu. A year later, Shu Han troops declared war on Wu and met the Wu armies at the Battle of Yiling. At Yiling, Liu Bei was disastrously defeated by Sun Quan's commander Lu Xun and forced to retreat back to Shu, where he died soon afterward. After the death of Liu Bei, Shu and Wu resumed friendly relations at the expense of Wei, thus stabilizing the tripartite configuration. In 222, Sun Quan renounced his recognition of Cao Pi's regime and, in 229, he declared himself emperor at Wuchang.
Dominion of the north completely belonged to Wei, whilst Shu occupied the southwest and Wu the central south and east. The external borders of the states were generally limited to the extent of Chinese civilization. For example, the political control of Shu on its southern frontier was limited by the Tai tribes of modern Yunnan and Burma, known collectively as the Southern Barbarians (南蠻).
Consolidation
In 223 Liu Shan rose to the throne of Shu following his father's defeat and death. The defeat of Liu Bei at Yiling ended the period of hostility between Wu and Shu and both used the opportunity to concentrate on internal problems and the external enemy of Wei. For Sun Quan, the victory terminated his fears of Shu expansion into Jing province and he turned to the aborigines of the southeast, whom the Chinese collectively called the "Shanyue" peoples . A collection of successes against the rebellious tribesmen culminated in the victory of 224. In that year Zhuge Ke ended a three year siege of Danyang with the surrender of 100,000 Shanyue. Of these, 40,000 were drafted as auxiliaries into the Wu army. Meanwhile Shu was also experiencing troubles with the indigenous tribes of their south. The Southwestern Nanman peoples rose in revolt against Han authority, captured and looted the city of Yizhou. Zhuge Liang, recognising the importance of stability in the south, ordered the advance of the Shu armies in three columns against the Nanman. He fought a number of engagements against the chieftain Meng Huo, at the end of which Meng submitted. A tribesman was allowed to reside at the Shu capital Chengdu as an official and the Nanman formed their own battalions within the Shu army.
Zhuge Liang's Northern Expedition
At the end of Zhuge Liang's southern campaign, the Wu-Shu alliance came to fruition and Shu was free to move against the north. In 227 Zhuge Liang transferred his main Shu armies to Hanzhong, and opened up the battle for the northwest with Wei. The next year, he ordered the general Zhao Yun to attack from Ji Gorge as a diversion while Zhuge himself led the main force to Qishan. The vanguard Ma Su, however, suffered a tactical defeat at Jieting and the Shu army was forced to withdraw. In the next six years Zhuge Liang attempted several more offensives, but supply problems limited the capacity for success. In 234 he led his last great northern offensive, reaching the Battle of Wuzhang Plains south of the Wei River. Due to the death of Zhuge Liang (234 AD), however, the Shu army was forced once again to withdraw, but were pursued by Wei. The Shu forces began to withdraw; Sima Yi deduced Zhuge's demise and ordered an attack. Shu struck back almost immediately, causing Sima Yi to second guess and allow Shu to withdraw successfully.
Wu and the South
In the times of Zhuge Liang's great northern offensives, the state of Wu had always been on the defensive against invasions from the north. The area around Hefei was the scene of many bitter battles and under constant pressure from Wei after the Battle of Red Cliffs. Warfare had grown so intense that many of the residents chose to migrate and resettle south of the Yangzi. After Zhuge Liang's death, attacks on the Huainan region intensified but nonetheless, Wei could not break through the line of the river defenses erected by Wu, which included the Ruxu fortress.
Sun Quan's long reign is regarded as a time of plenty for his southern state. Migrations from the north and the settlement of the Shanyue increased manpower for agriculture, especially along the lower reaches of the Yangzi and in Kuaiji commandery. River transport blossomed, with the construction of the Zhedong and Jiangnan canals. Trade with Shu flourished, with a huge influx of Shu cotton and the development of celadon and metal industries. Ocean transport was improved to such an extent that sea journeys were made to Manchuria and the island of Taiwan. In the south, Wu merchants reached Linyi (northern Vietnam) and Fu'nan (southern Vietnam). As the economy prospered, so too did the arts and culture. In the Yangzi delta, the first Buddhist influences reached the south from Luoyang.
Decline and End of the Three Kingdom
From the late 230s tensions began to become visible between the imperial Cao clan and the Sima clan. Following the death of Cao Zhen, factionalism was evident between Cao Shuang and the Grand Commander Sima Yi. In deliberations, Cao Shuang placed his own supporters in important posts and excluded Sima, whom he regarded as a threat. The power of the Sima clan, one of the great landowning families of the Han, was bolstered by Sima Yi's military victories. Additionally, Sima Yi was an extremely capable strategist and politician. In 238 he crushed the rebellion of Gongsun Yuan and brought the Liaodong region directly under central control. Ultimately, he outmaneuvered Cao Shuang in power play. Taking advantage of an excursion by the imperial clansmen to the Gaoping tombs, Sima undertook a putsch in Luoyang, forcing Cao Shuang's faction from authority. Many protested against the overwhelming power of the Sima family; notable among these were the Seven Sages of the Bamboo Grove. One of the sages, Xi Kang, was executed as part of the purges after Cao Shuang's downfall.
Fall of Shu
The decreasing strength of the Cao clan was mirrored by the decline of Shu. After Zhuge Liang's death, his position as Lieutenant Chancellor fell to Jiang Wan, Fei Yi and Dong Yun, in that order. But after 258, Shu politics became increasingly controlled by the eunuch faction and corruption rose. Despite the energetic efforts of Jiang Wei, Zhuge's protege, Shu was unable to secure any decisive achievement. In 263, Wei launched a three-pronged attack and the Shu army was forced into general retreat from Hanzhong. Jiang Wei hurriedly held a position at Jian'ge but he was outflanked by the Wei commander Deng Ai, who force-marched his army from Yinping through territory formerly considered impassable. By the winter of the year, the capital Chengdu fell due to the strategic invasion of Wei by Deng Ai who invaded Chengdu personally. The emperor Liu Shan thus surrendered. The state of Shu had come to an end after forty-three years.
Fall of Wei
Cao Huan succeeded to the throne in 260 after Cao Mao was killed by Sima Zhao. Soon after, Sima Zhao died and his title as Lord of Jin was inherited by his son Sima Yan. Sima Yan immediately began plotting to become Emperor but faced stiff opposition. However, due to advice from his advisors, Cao Huan decided the best course of action would be to abdicate, unlike his predecessor Cao Mao. Sima Yan seized the throne in 264 after forcing Cao Huan's abdication, effectively overthrowing the Wei Dynasty and establishing the successor Jin Dynasty. This situation was similar to the deposal of Emperor Xian of the Han Dynasty by Cao Pi, the founder of the Wei Dynasty.
Fall of Wu
Following Sun Quan's death and the ascension of the young Sun Liang as emperor in 252, the kingdom of Wu went into a period of steady decline. Successful Wei suppression of rebellions in the Huainan region by Sima Zhao and Sima Shi reduced any opportunity of Wu influence. The fall of Shu signalled a change in Wei politics. After Liu Shan surrendered to Wei, Sima Yan (grandson of Sima Yi), overthrew the Wei emperor and proclaimed his own dynasty of Jin in 264, ending forty-six years of Cao dominion in the north. After Jin's rise, Emperor Sun Xiu of Wu died, and his ministers gave the throne to Sun Hao. Sun Hao was a promising young man, but upon ascension he became a tyrant, killing or exiling all who dared oppose him in the court. In 269 Yang Hu, Jin commander in the south, started preparing for the invasion of Wu by ordering the construction of a fleet and the training of marines in Sichuan under Wang Jun. Four years later, Lu Kang, the last great general of Wu, died leaving no competent successor. The planned Jin offensive finally came in the winter of 279. Sima Yan launched five simultaneous offensives along the Yangzi River from Jianye to Jiangling whilst the Sichuan fleet sailed downriver to Jing province. Under the strain of such an enormous attack, the Wu forces collapsed and Jianye fell in the third month of 280. Emperor Sun Hao surrendered and was given a fiefdom on which to live out his days. This marked the end of the Three Kingdoms era, and the beginning of a break in the forthcoming 300 years of chaos.
Population
The Sanguo Zhi contains population figures for the three kingdoms. As with many Chinese historical population figures, these numbers are likely to be less than the actual populations, since census and tax records went hand in hand, and tax evaders were often not on records.
Three Kingdoms Period Populations Year Households Population Note
Eastern Han Dynasty, AD 156 10,679,600 56,486,856
Shu Han, AD 221 200,000 900,000
Shu Han, AD 263 280,000 1,082,000 At Shu's demise, the population contained 102,000 armed soldiers and 40,000 various officials.
Wu, AD 238 520,000 2,567,000
Wu, AD 280 530,000 2,535,000 At Wu's demise, the population had 32,000 officials, 230,000 soldiers, and 5,000 imperial concubines.
Cao Wei, AD 260 663,423 4,432,881
Western Jin, AD 280 2,495,804 16,163,863 After reuniting China, the Jin Dynasty's population was greatest around this time.
From Zou Jiwan (Chinese: 鄒紀萬), Zhong Guo Tong Shi - Wei Jin Nan Bei Chao Shi 中國通史·魏晉南北朝史, (1992).
While it is clear that warfare undoubtedly took many lives during this period, the census figures do not support the idea that millions were wiped out solely from warfare. Other factors such as mass migration out of China must be taken into account.
Economy
In economic terms the division of the Three Kingdoms reflected a reality that long endured. Even in the Northern Song, seven hundred years after the Three Kingdoms, it was possible to think of China as being composed of three great regional markets. (The status of the northwest was slightly ambivalent, as it had links with the northern region and Sichuan). These geographical divisions are underscored by the fact that the main communication routes between the three main regions were all man-made: the Grand Canal linking north and south, the hauling-way through the Three Gorges of the Yangzi linking southern China with Sichuan and the gallery roads joining Sichuan with the northwest. The break into three separate entities was quite natural and even anticipated by such political foresight as that of Zhuge Liang .
The Three Kingdoms in popular culture
Numerous people and affairs from the period later became Chinese legends. The most complete and influential example is the historical fiction Romance of the Three Kingdoms, written by Luo Guanzhong during the Ming dynasty. Fictional accounts of the Three Kingdoms, mostly based on the Romance, play a significant role in East Asian popular culture. Books, TV serials, movies, cartoons/anime, games, and music on the topic are still regularly produced in China, Taiwan, South Korea and Japan.
