• Arab conquests outside Arabia began under second caliph, Umar
• Umayyad caliphs presided over Arab realm rather than religious empire
  • Ruled with armies consisting almost entirely of Muslim Arabs
  • Caliphs gradually replaced non-Muslims and introduced Arabic
  • Umayyad dynasty fell in 750 after decade of growing unrest
• Umayyad Spain developed distinctive Islamic culture due to separation
• In 750, last Umayyad caliph was overthrown, establishing Abbasid Caliphate