Narmer is the early pharaoh most commonly credited with unifying Upper and Lower Egypt around 3100 BC.
Narmer ruled at the transition from Egypt’s Predynastic Period to the Early Dynastic Period and is widely regarded as the founder of the First Dynasty. The famous Narmer Palette shows him wearing both the white crown of Upper Egypt and the red crown of Lower Egypt, imagery strongly associated with the union of the Two Lands.
The identification is not completely free of debate. Ancient Egyptian and later Greek traditions name the first ruler of unified Egypt as Menes, while most modern Egyptologists identify Menes with Narmer. A minority view identifies Menes with Hor-Aha, Narmer’s successor. Even so, Narmer is the standard archaeological answer because contemporary artifacts provide the clearest evidence connecting him with unification.
The process may have taken place over several campaigns rather than in one single event. Narmer’s reign is generally placed near the end of the fourth millennium BC, often around 3100 BC, though Egyptian chronology is approximate.