A caliphate (Arabic: خِلَافَةْ, khilāfah) is an institution or public office under the leadership of an Islamic steward with the title of caliph (خَلِيفَةْ khalīfa ), a person considered a political–religious successor to the Islamic prophet Muhammad and a leader of the entire Muslim world (ummah). Historically, the caliphates were polities based on Islam which developed into multi-ethnic trans-national empires.
