大約在公元前3150年，上下埃及的統一標志著古埃及早王朝時期的開始。早王朝時期包括了第一王朝與第二王朝，時間由前王朝時期直至公元前2686年，又或者直至古王國時期。在第一王朝時期，埃及的首都由阿拜多斯遷至孟斐斯，統治埃及的君主擁有神一般的權力，其統治範圍由尼羅河三角洲至阿斯旺尼羅河第一瀑布。阿拜多斯仍然埃及南部宗教崇拜的中心。古埃及文明的許多成就，如藝術、建築及宗教的各方面都在這段時期成形。
在上下埃及統一之前，埃及的各個城市都有自主權。在早王朝時期，以及後來的許多時間，埃及均被稱為“兩地”（Two Lands）。法老建立國傢的行政及委任王室政府官員。中央政府的建築是典型以木或砂岩建造的開放式神廟。埃及的國傢組成基本上是本土的，上下埃及的人民的交談很可能使用共同語，即埃及語，而各地則有方言，促成了國傢的統一。而最早期的埃及象形文字於早王國時期之前出現，儘管我們無法透過那時的文字確定其口語。
根據曼涅托，第一位埃及的君主為美尼斯。但是，最早期有記錄的第一王朝君主是荷爾-阿哈，以及第一位統一兩地的君主那爾邁（前王朝時期的最後一位君主）——他的名字刻於一塊古埃及人用作畫眼綫的磨板上，而後世稱這塊磨板為那爾邁石板。
農民的喪葬儀式與前王朝時期相同，但富有人傢則要求更多。因此，埃及人開始興建馬斯塔巴，成為了古王國時期如階梯金字塔的前身。𠔌類農業及中央化令埃及在接下來的800年都得到興盛的發展。
The Archaic or Early Dynastic Period of Egypt immediately follows the unification of Lower and Upper Egypt c. 3100 BC. It is generally taken to include the First and Second Dynasties, lasting from the Protodynastic Period of Egypt until 2686 BC, or the beginning of the Old Kingdom. With the First Dynasty, the capital moved from Abydos to Memphis where an Egyptian god-king ruled a now unified polity that extended from the Nile Delta to the first cataract at Aswan. Abydos remained the major holy land in the south. The distinctive hallmarks of ancient Egyptian civilization, such as art, architecture and many aspects of religion, took shape during the Early Dynastic period.
Before the unification of Egypt, the land was settled with autonomous villages. With the early dynasties, and for much of Egypt's history thereafter, the country came to be known as the Two Lands. The rulers established a national administration and appointed royal governors. The buildings of the central government were typically open-air temples constructed of wood or sandstone. State formation in Egypt was primarily indigenous in character, and it is likely that a common language, namely Egyptian, was spoken in Upper and Lower Egypt in variant dialects, which facilitated the unification. The earliest hieroglyphs appear just before this period, though nothing is certain about the spoken language represented by the writing at the time.
According to Manetho, the first king was Menes. However, the earliest recorded king of the First Dynasty was Hor-Aha, and the first king to claim to have united the two lands was Narmer (the final king of the Protodynastic Period). His name is known because it is written on a votive palette used for grinding minerals for kohl, used by ancient Egyptians to outline the eyes. Funeral practices for the peasants would have been the same as in predynastic times, but the rich demanded something more. Thus, the Egyptians began construction of the mastabas which became models for the later Old Kingdom constructions such as the Step pyramid. Cereal agriculture and centralization contributed to the success of the state for the next 800 years.
It has also so been interpreted that King Menes and the whole traditional story of an Egypt unified under a single conquering ruler, who led his armies and conquered lower Egypt to establish the first dynasty in the lower Egyptian city of Memphis, is just mythology as are the twin kingdoms story. It seems certain that Egypt became unified as a cultural and economic domain long before its first king ascended to the throne in the lower Egyptian city of Memphis where the dynastic period did originate. Political unification proceeded gradually, perhaps over a period of a century or so as local districts established trading networks and the ability of their governments to organize agriculture labor on a larger scale increased, divine kingship may also have gained spiritual momentum as the cults of gods like Horus, Seth and Neith associated with living representatives became wide spread in the country.