answers: around 3100 BC
context: three millennia. Egyptian culture flourished during this long period and remained distinctively Egyptian in its religion, arts, language and customs. The first two ruling dynasties of a unified Egypt set the stage for the Old Kingdom period ("c". 2700–2200 BC), which constructed many pyramids, most notably the Third Dynasty pyramid of Djoser and the Fourth Dynasty Giza Pyramids. The First Intermediate Period ushered in a time of political upheaval for about 150 years. Stronger Nile floods and stabilization of government, however, brought back renewed prosperity for the country in the Middle Kingdom "c". 2040 BC, reaching a peak during the </s> Ancient Egypt Ancient Egypt was a civilization of ancient North Africa, concentrated along the lower reaches of the Nile River in the place that is now the country Egypt. Ancient Egyptian civilization followed prehistoric Egypt and coalesced around 3100 BC (according to conventional Egyptian chronology) with the political unification of Upper and Lower Egypt under Menes (often identified with Narmer). The history of ancient Egypt occurred as a series of stable kingdoms, separated by periods of relative instability known as Intermediate Periods: the Old Kingdom of the Early Bronze Age, the Middle Kingdom of the Middle Bronze Age and the </s> agriculture and the construction of large buildings. At this time, Egyptians in the southwestern corner of Egypt were herding cattle and also constructing large buildings. Mortar was in use by the 4th millennium. The people of the valley and the Nile Delta were self-sufficient and were raising barley and emmer, an early variety of wheat, and stored it in pits lined with reed mats. They raised cattle, goats and pigs and they wove linen and baskets. Prehistory continues through this time, variously held to begin with the Amratian culture. Between 5500 BC and the 31st century BC, small settlements flourished
question: when did the civilization of ancient egypt begin