Unity was eventually restored to Egypt in about 2050 BCE by one of the Theban princes, Mentuhotep II of the Eleventh Dynasty. The reunification marks the beginning of the Middle Kingdom. Mentuhotep's progress in reuniting Egypt can be seen in three successvie Horus names he took for himself. "He who breaths life into the heart of the Two Lands' was the first expression of his desire to unify the country. Then, as if to stress his southern origins: "Divine is the White Crown [of southern Egypt]" and finally, in the thirty-ninth year of his reign when he felt totally secure, "He who unifies the Two Lands."

Mentuhotep's concerns went further than unification. He secured the borders of Egypt against raiding nomads and then extended Egyptian influence down into Nubia with all the riches it offered. Mentuhteop and his successors of the Twelfth Dynasty aimed at a total domination of the area and its peoples. Their power was expressed in a series of elaborately constructed forts on the Nile between the First and Second Cataracts. When Mentuhotep died, he was buried in one of the finest monuments of the Middle Kingdom, a great funerary complex set against a natural amphitheater of rock on the west bank at Thebes. As if establishing its links with an older Egypt, the complex has a valley temple, a causeway, 950 meters long, flanked by statues of the king in the form of Osiris and a mortuary temple. What it lacks is a pyramid (although some experts believe that one may have been built on the roof of the mortuary temple). the body was buried under the cliff face itself, while alongside the main complex are the tombs of six 'queens', wives or concubines of Mentuhotep.

For the time being no more royal burials took place at Thebes. The Eleventh Dynasty was replaced by the Twelfth about 1985 BCE when one Amenemhat seized power. Amenemhat I, who was probably originally a vizier, and his successors were among the most successful kings in Egyptian history. Seeking to strengthen his position strategically, Amenemhat found a new capital at Itj-tawy in Middle Egypt (its full name reads "it is Amenemhat who has conquered the Two Lands"), although Thebes was retained as the administrative center of Upper Egypt. Amenemhat also set a new tradition of using his son as co-regent so that power could pass more smoothly on a king's death.