The Eleventh Dynasty pharaohs all ruled from Thebes, however, the first four kings are often placed within the First Intermediate Period and Montuhotep Nebhetepre (Montuhotep II) is described as the first pharaoh of the Middle Kingdom. Manetho states that the Eleventh Dynasty consisted of sixteen kings based in Thebes, who reigned for a total of forty-three years. However, this contrast with the Turin King List which names only seven kings ruling for a total of one hundred and forty-three years. It is generally accepted that the Turin list is more accurate, but that Manetho was right in asserting that they were based in Thebes.
The Dynasty begins either with Montuhotep I, (a nomarch from Thebes) or his son Intef Sehertawy (Intef I). Their successor Intef Wahankh (Intef II) asserted his position as the ruler of all of Egypt, bringing him into a confrontation with the rulers of the Tenth Dynasty (based in Herakleopolis Magna). Intef led a number of raids and successfully captured the nome of Abydos but did not manage to reunite the whole country. This job was left to Montuhotep Nebhetepra (Montuhotep II). When he defeated the Herakleopolitan princes, he began re-establishing Egyptian power over Africa and the Near East and reopened a number trade routes.
Little is known about the last pharaoh of the dynasty, Montuhotep Nebtawyra (Montuhotep IV). However, there is some evidence that his vizier, Amenemhat, engineered a coup d'etate and installed himself as Amenemhat I, the first king of the Twelfth Dynasty.
The twelth dynasty was one of the most stable periods of Egyptian history. Powerful rulers expanded Egyptian territory into Canaan and Nubia. Egyptian literature produce such gems as the "Story of Sinuhe", the "Tale of the Eloquent Peasant" and the "Instructions of Amenemhat" and scholars composed numerous medical, mathematical and legal papyrus.
With the demise of the twelth dynasty central control waned and although some scholars include the thirteenth dynasty in the Middle Kingdom, it was a shadow of its illustrious predecessor. The fourteenth dynasty (also sometimes included in the Middle Kingdom) ruled concurrently with the end of the thirteenth dynasty as a small breakaway kingdom located in the Delta. I have included both dynasty thirteen and fourteen in the Second Intermediate Period.