In Arabic, caliph means "a successor to the prophet". This is what leaders of the Islamic faith came to be called. Their rule is called a caliphate.

Map of caliphate

Some of the early leaders of the Muslim community following Muhammad's (570–632) death called themselves "Khalifat Allah", meaning representative of God. But the other title of "Khalifat rasul Allah", meaning the successor to the prophet of God, became the common title. Some academics write the term as Khalīf.