The Middle East region, comprising the Arabian Peninsula, Mesopotamia and the Levant, contains within it the three earliest centres o f Islamic civilisation: the Hejaz, dominated by Mecca and Medina, where the Prophet M uhammad preached and where the first Islamic com­ munity developed under his aegis and that o f the first three caliphs; greater Syria, centred on Damascus, the capital o f the Umayyad dynasty from 661 to 750, and containing Jerusalem, Islam’s first qibla and its third holy city; and Iraq, where the new capital o f Baghdad became the centre o f a vast empire under the Abbasids, where the consensus that grew into Islamic orthodoxy was first hammered out, and where the chief elements o f classical Islamic civilisation were developed.