(Arabic; " Rightly Guided ")
First four caliph s of the Islamic community: Ab 016B; Bakr , Umar ibn al-Khatt 0101; b , Uthm 0101; n ibn Aff 0101; n , and Al 012B; .
As Islam 's first rulers after Muhammad , they assumed all his duties except prophecy: they led the congregation in prayer, delivered the Friday sermons, and commanded the army. The caliphate of the Rash 012B; d 016B; n expanded the Islamic state beyond Arabia into Iraq, Syria, Palestine, Egypt, Iran, and Armenia. They were also responsible for the adoption of the Islamic calendar and the establishment of an authoritative reading of the Qur 0101; n .