Beneath the source problem there is a life whose outline commands broad agreement, even where the detail is debated.
He was born in Mecca around 570, into the clan of Hashim of the tribe of Quraysh, and orphaned young; the traditional account has him raised by his grandfather and then his uncle Abu Talib, and working the caravan trade. His marriage to Khadija, a merchant widow, is placed before the preaching began. The tradition dates the first revelation to about 610, on Mount Hira near Mecca, and describes private and then public preaching of one God against the polytheism of the sanctuary, which drew the opposition of the Quraysh, whose prestige was bound up with it.
The turning point is the hijra, the migration to Medina (then Yathrib) in 622. It is from this event, not his birth or the first revelation, that the Islamic calendar counts its years. At Medina he was not only a preacher but the arbiter and leader of a community that included the town's Arab clans and its Jewish tribes, an arrangement recorded in the document later called the Constitution of Medina.
The years that followed are, in the traditional narrative, of conflict with Mecca, Badr, Uhud, the Trench, ending in the largely peaceful submission of Mecca around 630 and the clearing of the Kaaba of its idols. He died at Medina in 632, having brought most of the Arabian tribes into some relation with the new polity. That much is the frame within which the source-critical arguments are conducted.