Short answers, pulled from the story.
Djoser was the first king of the Old Kingdom of Egypt. He ordered the construction of the step pyramid at Saqqara, which marked the transition from simple mastaba tombs to monumental stone architecture.
The Old Kingdom of Egypt spanned from 2686 BC to 2181 BC. This era covers the Third Dynasty through the Sixth Dynasty and represents the first sustained peak of civilization in the lower Nile Valley.
The capital of the Old Kingdom of Egypt remained at Ineb-Hedj, known today as Memphis. The architecture of the royal residence and necropolis in this location signaled a new level of centralized authority.
The Old Kingdom of Egypt collapsed due to a combination of internal power struggles and environmental factors. The 22nd century BC drought prevented the normal flooding of the Nile, leading to decades of famine and civil wars after the reign of Pepi II.
A 2025 study published in Nature found that an Old Kingdom adult male had 77.6% North African Neolithic ancestry and 22.4% ancestry related to Neolithic Mesopotamia. This genetic profile suggests ancient migration flows from the eastern Fertile Crescent to Egypt.