Excerpts from Books and Wikipedia
"A massive irrigation project transformed the oasis of Faiyum, southwest of Memphis, into a great breadbasket for the kingdom; watered by a 300-foot-wide canal from the Nile, Faiyum covered hundreds of square miles. . . . Shortly after 2000 B.C., troops of Pharaoh Amenemhet I embarked on the first in a series of conquests that brought much of Nubia under Egyptian control." [National Geographic Almanac, p. 53] "Minor rulers" were pharaohs in Dynasty 13-14 (1795-1650 BC) of the Middle Kingdom. [Smithsonian, p. 468] "The prosperity of the Middle Kingdom lasted for a relatively short time. The rule of Senusret III’s son, Amenemhet III, was its high point. When he died, the power of the pharaoh to hold the country safe against invaders, and united with itself, began to fade." [Bauer: Ancient World, p. 178]