新巴比倫王國（前626年－前539年），由迦勒底人所建，大約處於古代美索不達米亞南部。公元前626年建立，在尼布甲尼撒二世統治時國勢達到鼎峰，最後在公元前539年被波斯人消滅。
建立
新巴比倫王國由迦勒底人建立，迦勒底人是閃米特人的一支，他們於公元前1000年代初來到兩河流域南部定居，隨後亞述帝國徵服並統治了兩河流域南部，迦勒底人曾多次起義反抗亞述的統治。
公元前626 年，亞述人派迦勒底人領袖那波帕拉沙爾率軍駐守巴比倫，他到巴比倫後，卻發動反對亞述統治的起義，建立新巴比倫王國，並與伊朗高原的米底王國聯合，共同對抗亞述。公元前612年，亞述帝國結束，遺産被新巴比倫王國及米底王國瓜分，其中新巴比倫王國分取了亞述帝國的西半壁河山，即兩河流域南部、敘利亞、巴勒斯坦及腓尼基。
強盛期
公元前604年，尼布甲尼撒二世即位，敘利亞立時歸順新巴比倫王國，但腓尼基及巴勒斯坦地區態度不明，而埃及一嚮覬覦此區，拉攏推羅、西頓等腓尼基地區與埃及結盟。對此，尼布甲尼撒二世繼續與米底王國結盟，又娶米底公主阿米蒂斯為後，以鞏固自己後方。公元前597年，出兵巴勒斯坦，攻占耶路撒冷，扶植猶太人齊德啓亞為傀儡統治猶太人。
公元前590年，埃及法老普薩姆提剋出兵巴勒斯坦，推羅國王投靠埃及，西頓被占領，猶太人齊德啓亞及巴勒斯坦、外約旦等地紛紛倒嚮埃及。同時，米底王國與新巴比倫王國的關係緊張起來，為此新巴比倫王國築起一條新長城防範米底人。然而，米底因要對抗烏拉爾圖及西徐亞人，無力再與新巴比倫王國對抗，致使尼布甲尼撒二世可於公元前587年第二次揮軍巴勒斯坦。他圍困猶太人的聖城耶路撒冷，齊德啓亞突圍失敗，落入新巴比倫王國軍隊之手，被挖去雙眼後送往巴比倫尼亞。公元前586年，耶路撒冷被圍十八個月後城陷，居民被俘往巴比倫尼亞，史稱“巴比倫之囚”。
尼布甲尼撒二世又圍攻腓尼基的推羅，不果。公元前574年，雙方議和，推羅國王伊托巴爾三世承認尼布甲尼撒二世為尊者，保持了推羅的自治地位，其他附近的小王國都紛紛嚮尼布甲尼撒二世稱臣、公元前569年，埃及發生王位之爭，尼布甲尼撒二世曾趁此在公元前567年入侵埃及，結果不詳，但迫使埃及放棄侵略巴勒斯坦的野心。
尼布甲尼撒二世統治時的巴比倫城市圖
尼布甲尼撒二世對巴比倫城進行入大模模建設，使巴比倫城成為當時世上最繁華的城市，也是中東最重要的工商業城市。巴比倫城以兩道圍墻圍繞．外墻以外，還有一道註滿了水的壕溝及一道土堤，城內的主幹道中央以白色及玫瑰色石板鋪成，另城有八個城門，其中的北門就是著名的伊絲達爾門，表面用青色琉璃磚裝飾，磚上有許多公牛和神話中的怪物等浮雕。巴比倫城被建設得宏偉壯麗，直到100多年後，希臘歷史學家，被稱為“歷史之父”的希羅多德來到巴比倫城時，仍稱它為世界上最壯麗的城市。
尼布甲尼撒二世的傑作，古代世界七大奇觀之一，空中花園
尼布甲尼撒二世還在巴比倫城為米底來的王後興建“空中花園”，令米底的公主不再有思鄉之苦。該花園位於底格裏斯河邊，據狄奧多拉記載，花園每邊長120米左右，呈正方形，花園內滿是奇花異草，並用蠃旋泵不斷地從幼發拉底河裏取水作灌溉。這個花園遠看起來就像位於天空中般，因此被稱為空中花園。內裏亦有着富麗堂皇的宮殿，使得尼布甲尼撒二世和王後可以在宮殿裏飽覽全城的景色。這個空中花園名滿天下，被後世譽為古代世界七大奇觀之一，空中花園被毀於公元前三世紀。
新巴比倫王國時期的奴隸制度也有了更大的發展，
(這一段真是太非理了,因為當有了資産就不能做奴隸了,奴隸本來是無産階級.所以可說,這樣的社會是幻想社會無實的,請維基檢查!)。然而，大多數的奴隸的處境仍然是很不好，從保存下來的司法文件中，奴隸否認自己是奴隸的身分，還以逃亡形式進行反抗，所以買賣奴隸時，賣主必須嚮買主保證奴隸不逃亡。除奴隸外，社會上主要的生産者是自由民，他們租佃王室、神廟及個別奴隸主的土地，而且往往還要額外租用牲畜、種子和農具，他們也同時是當時的被剝削者。
覆亡
尼布甲尼撒二世死後不久，國內階級矛盾及民族矛盾加劇，最後一個國王那波尼達統治時，國王及馬爾杜剋神廟之間的矛盾加劇，並試圖另立新神，那波尼達離開首都，以其子伯沙撒攝政。公元前539年，波斯人崛起，居魯士二世率軍入侵新巴比倫王國時，祭司竟打開大門放波斯軍隊入城，伯沙撒被殺，那波尼達被俘，新巴比倫王國不戰而亡。
考古發現
19世紀下半葉，在巴格達附近發掘出很多泥版和圓柱，使人對古巴比倫的歷史認識大增。其中之一是深具價值的一份文獻，稱為拿波尼度編年史，現今收藏於大英博物館。巴比倫王拿波尼度曾與兒子伯沙撒共同攝政。但他比兒子活得更久，後者於公元前539年10月5日的晚上在居魯士手下的軍隊攻陷巴比倫時被殺。拿波尼度編年史就巴比倫的陷落提供一項註明日期的記錄，幫助確定事件發生的時間。以下是拿波尼度編年史一小部分的翻譯：“塔斯利都月(提斯利月（9/10 月）)，居魯士在底格裏斯河的俄庇斯襲擊阿卡得的軍隊。……月中第14日，西巴爾不戰而降，拿波尼度逃離該城。第16日(儒略歷公元前539年10月11 日；格雷果裏歷10月5日)古提恩的總督戈布利亞（烏格巴魯）連同居魯士的軍隊不用動刀便進入巴比倫城。其後，拿波尼度在返回巴比倫時被捕。……亞拉沙姆努月(赫捨萬月（10/11月）)第3日［儒略歷10月28日］，居魯士進入巴比倫，居民將青緑的樹枝鋪在他腳前——他宣佈‘和平’(sulmu)臨到城中。居魯士嚮巴比倫全境致意。他的總督戈布利亞在巴比倫設立（輔）總督。”
新巴比倫王列表
* 那波帕拉沙爾 (Nabopolassar) 公元前626年 - 公元前605年
* 尼布甲尼撒二世 (Nebuchadnezzar II) 公元前605年 - 公元前562年
* 以未米羅達 (Evil-Merodach/Amel-Marduk) 公元前562年 - 公元前560年
* 涅裏格利沙爾 (Neriglissar/Nergal-sharezer) 公元前560年 - 公元前556年
* 拉巴施馬爾杜剋 (Labashi-Marduk) 公元前556年
* 那波尼達 (Nabonidus) 公元前556年 - 公元前539年
* 伯沙撒 (Belshazzar) 攝政王，公元前553年或前549年 - 公元前539年
Through the centuries of Assyrian domination, Babylonia enjoyed a prominent status, or revolted at the slightest indication that it did not. The Assyrians always managed to restore Babylonian loyalty, however, whether through granting of increased privileges, or militarily. That finally changed in 627 BC with the death of the last strong Assyrian ruler, Assurbanipal, and Babylonia rebelled under Nabopolassar the Chaldean the following year. With help from the Medes, Nineveh was sacked in 612 BC, and the seat of empire was again transferred to Babylonia.
Nabopolassar was followed by his son Nebuchadnezzar II, whose reign of 43 years made Babylon once more the mistress of the civilized world, including the conquering of Phoenicia in 585 BC. Only a small fragment of his annals has been discovered, relating to his invasion of Egypt in 567 BC, and referring to "Phut of the Ionians".
Of the reign of the last Babylonian king, Nabonidus (Nabu-na'id), and the conquest of Babylonia by Cyrus, there is a fair amount of information available. This is chiefly derived from a chronological tablet containing the annals of Nabonidus, supplemented by another inscription of Nabonidus where he recounts his restoration of the temple of the Moon-god at Harran; as well as by a proclamation of Cyrus issued shortly after his formal recognition as king of Babylonia. It was in the sixth year of Nabonidus (549 BC) that Cyrus, the Achaemenid Persian "king of Anshan" in Elam, revolted against his suzerain Astyages, "king of the Manda" or Medes, at Ecbatana. Astyages' army betrayed him to his enemy, and Cyrus established himself at Ecbatana, thus putting an end to the empire of the Medes. Three years later Cyrus had become king of all Persia, and was engaged in a campaign in northern Mesopotamia. Meanwhile, Nabonidus had established a camp in the desert, near the southern frontier of his kingdom, leaving his son Belshazzar (Belsharutsur) in command of the army.
In 539 BC Cyrus invaded Babylonia. A battle was fought at Opis in the month of June, where the Babylonians were defeated; and immediately afterwards Sippara surrendered to the invader. Nabonidus fled to Babylon, where he was pursued by Gobryas, and on the 16th day of Tammuz, two days after the capture of Sippara, "the soldiers of Cyrus entered Babylon without fighting." Nabonidus was dragged from his hiding-place, where the services continued without interruption. Cyrus did not arrive until the 3rd of Marchesvan (October), Gobryas having acted for him in his absence. Gobryas was now made governor of the province of Babylon, and a few days afterwards the son of Nabonidus died. A public mourning followed, lasting six days, and Cambyses accompanied the corpse to the tomb.
Cyrus now claimed to be the legitimate successor of the ancient Babylonian kings and the avenger of Bel-Marduk, who was assumed to be wrathful at the impiety of Nabonidus in removing the images of the local gods from their ancestral shrines to his capital Babylon. Nabonidus, in fact, had excited a strong feeling against himself by attempting to centralize the religion of Babylonia in the temple of Merodach (Marduk) at Babylon, and while he had thus alienated the local priesthoods, the military party despised him on account of his antiquarian tastes. He seems to have left the defense of his kingdom to others, occupying himself with the more congenial work of excavating the foundation records of the temples and determining the dates of their builders.
The invasion of Babylonia by Cyrus was doubtless facilitated by the existence of a disaffected party in the state, as well as by the presence of foreign forced exiles like the Jews, who had been planted in the midst of the country. One of the first acts of Cyrus accordingly was to allow these exiles to return to their own homes, carrying with them the images of their god and their sacred vessels. The permission to do so was embodied in a proclamation, whereby the conqueror endeavored to justify his claim to the Babylonian throne. The feeling was still strong that none had a right to rule over western Asia until he had been consecrated to the office by Bel and his priests; and accordingly, Cyrus henceforth assumed the imperial title of "King of Babylon."