Caliphate: A caliphate refers to an Islamic state led by a supreme political and religious leader known as a caliph. The concept of caliphate played a significant role in the expansion and governance of early Islamic empires.
Shia Islam: Shia Islam is another major branch of Islam that believes in the divine appointment of Ali, cousin and son-in-law of Prophet Muhammad, as his rightful successor. It differs from Sunni Islam in terms of leadership succession and certain theological beliefs.
Umayyad Empire: The Umayyad Empire was an early Islamic empire (661-750 CE) that emerged after the death of Ali, marking the split between Sunnis and Shias. It used Sunni Islam as a unifying force throughout its territories, including present-day Spain, North Africa, Middle East, and parts of Central Asia.