The Hijra: Muhammad’s emigration to Medina

By the end of the 610s Muhammad had won only a small following in Mecca. The leaders of the Quraysh answered his preaching with a boycott of his clan and the persecution of his followers, some of whom had already found refuge in Aksum, and after the death of his uncle and protector Abu Talib he looked for support outside his city. Yathrib, an agricultural oasis more than 400 km to the north, was shared by the Arab tribes of Aws and Khazraj, who had been at war with each other for generations, and by several Jewish tribes. Pilgrims from Yathrib met Muhammad at al-Aqaba near Mecca in 621 and again in 622, when seventy-five of them swore to protect him as they would their own wives and children.

Over about three months Muhammad’s Meccan followers left for Yathrib. Muslim tradition tells that the Quraysh then plotted to kill him, that Ali lay down in his bed to deceive the assassins, and that Muhammad and Abu Bakr hid for three days in a cave on Mount Thawr before setting out with a guide. They reached Quba, on the edge of the oasis, in September 622 — by the traditional date on 12 Rabiʿ al-Awwal, that is 24 September; some modern works give an earlier day. In Medina the emigrants (muhajirun) and the local “helpers” (ansar) formed a single community, whose relations with the other groups of the oasis were regulated by the document known as the Constitution of Medina.

The Hijra turned a persecuted group of believers into a political community able to wage war on Mecca and, within ten years, to bring most of Arabia under its rule. When Caliph Umar introduced a Muslim era in 637 or 638, he took as its starting point not the day of Muhammad’s arrival but the first day of that lunar year, 1 Muharram, which corresponds to 16 July 622 in the Julian calendar; years of this era are still marked AH (Anno Hegirae), and the Iranian solar calendar also counts from the Hijra. Nearly everything known about the event comes from biographies of Muhammad written more than a century later, the earliest surviving being that of Ibn Ishaq.