administrative division of ancient Egypt (Egypt, ancient). The system of dividing the country into nomes was definitely in force by the time of the Old Kingdom (c. 2575–c. 2130 BC) and persisted with modifications until the Muslim conquest (AD 640). In late times there were 42 nomes, or provinces, 22 in Upper and 20 in Lower Egypt. In Ptolemaic times, a heptanomis of seven nomes was formed in Middle Egypt. The Nile valley south of Ombos was sometimes regarded as one with the province of Nubia, although in the Old Kingdom Elephantine was considered the “door of the south.”

Each nome during the Old and Middle Kingdoms was administered by a nomarch, or district governor, who levied taxes, administered justice, and maintained an army.