How was the origin of islam?
The prophet Muhammad in the 7th century unified the Arabian Peninsula under a new faith, Islam, their expansion was really fast and it was divided:
Orthodox Caliphate (632-661): The caliphate was ruled by Muhammad’s family.
Omeya Caliphate (661-750): The Omeya family took over the Caliphate and moved the capital to Damascus.
Abbasid Caliphate (750-1258): the Omeyas were killed and the Abbasid family moved the capital to Baghdad. They were eventually conquered by the Turks, and the Caliphate slowly disintegrated.