The Middle Kingdom (c 2055—1786 BC). The rise of the Middle Kingdom began in a period of civil war. The struggle between the rulers of Thebes and Heracleopolis was finally decided in favor of the former and a series of rulers, called either Inyotef or Menthuhotpe, reunited the land and established the 11 Dyn. (2133—1991 BC). Menthuhotpe II (с 2060) took as his Horus name Smatowy (He-who—unites—the-Two Lands), and from this moment the Middle Kingdom begins. The most powerful kings were those of the following 12 Dyn. (1991—1786 BC) who organized Egypt again into a strong centralized state. They ruled from It-Towy, perhaps a suburb of Memphis originally thought to be a separate town. Expeditions were again sent to Libya, Nubia, and Sinai and extended to Syria and Punt.
To ensure continuity of government, the practice of co-regency was introduced, probably necessitated by the murder of the first king of the dynasty, Amenemhat I. The reigning king nominated one of his sons, not necessarily the eldest, to share the throne with him for the last years of his reign. Thus there should be a peaceful transfer of power on the king’s death. Steps were taken to limit the power of the nomarchs (the great nobles and governors) who had set up almost independent states within the country. As an initial measure, Amenemhat II reorganized the nome boundaries, but it was Senusert III, the greatest king of the dynasty, who finally broke their authority. Though his methods are not clear, after this time they posed no threat to the central government. Gradually, however, the internal strength of the kings declined and a period of weakness and disorganization, the Second Intermediate Period (c 1786—1567 BC), began. This existed during ﬁve dynasties, of which two are assigned to outsiders, i.e. Hyksos rulers, until the beginning of the 18 Dyn.