Abu Bakr (ca. 573-634) was the first caliph, or successor of Mohammed as ruler of the Arab state. He held together the political structure created by Mohammed at Medina, defeated separatist revolts, and initiated the expansion of Islam into Syria and Iraq.

Friend of Mohammed and three years younger, Abu Bakr was born in Mecca of the tribe of Quraysh and became a merchant. He was possibly the first mature man to accept Mohammed as the Prophet and to become a Moslem. After conversion he spent much of his wealth in buying and setting free Moslem slaves. However, his clan gave him little protection, and he suffered indignities from Mohammed's opponents. As Mohammed's closest friend and adviser, he alone accompanied him on his Hijra, the migration from Mecca to Medina in 622.

In Medina, Abu Bakr helped Mohammed in many unobtrusive ways, and his knowledge of the genealogies and intrigues of the numerous Arab tribes was a great asset. The two men were further bound together by Mohammed's marriage to Abu Bakr's daughter Aisha in 623 or 624. Abu Bakr did not command any important military expedition for Mohammed, but he was the leader of the pilgrimage to Mecca in 630 and was appointed to lead the public prayers during Mohammed's last illness. By signs as slight as these, he was marked out as caliph.

On Mohammed's death in June 632, the future of the state was uncertain, but the oratory of Omar (later the second caliph) persuaded the men of Medina to accept Abu Bakr as caliph. Much of his reign was occupied with quelling revolts. One had already broken out in Yemen, and soon there were about five others in different parts of Arabia. The leaders mostly claimed to be prophets, and the revolts are known as "the wars of the apostasy," though the underlying reasons were mainly political. The chief battle was that of Yamama in May 633, when Musaylima, the strongest insurgent leader, was defeated and killed by a Moslem army under Khalid ibn al-Walid.

Mohammed had foreseen the need for expeditions outside Arabia to absorb the energies of his Arab allies and prevent their fighting one another; and Abu Bakr, despite the threatening situation after Mohammed's death, sent an expedition from Medina toward Syria. As Arabia was pacified after the revolts, other expeditions were sent to Iraq, then a part of the Persian Empire, and to Syria. Shortly before Abu Bakr's death in August 634, his general Khalid, following a celebrated desert march from Iraq to Damascus, defeated a large Byzantine army at Ajnadain in Palestine and gave the Arabs a foothold in that country. Thus, in the short reign of Abu Bakr the embryonic Islamic state was not only preserved intact but was launched on the movement of expansion which produced the Arab and the Islamic empires.

Further Reading on Abu Bakr

There is no work solely on Abu Bakr by any Western scholar. His reign is briefly treated in Carl Brockelmann, History of the Islamic Peoples (1939; trans. 1947); Philip K. Hitti, History of the Arabs (1937; 8th rev. ed. 1963); and Bernard Lewis, The Arabs in History (1950).