A period in Egyptian history including the 11th through 13th Dynasties, c 2008-1630 BC. This phase began with the reunification of Upper and Lower Egypt by the 11th Dynasty king Mentuhotep II (Nebhapetre) ushering in years of stability and prosperity. It is usually divided into two phases, the early Middle Kingdom (late 11th and early 12th Dynasties) and the late Middle Kingdom (from the reign of Senusret III to end of 13th Dynasty).