A caliphate ( khilāfa) is a form of Islamic government led by a caliph ( )—a person considered a political and religious successor to the Islamic prophet, Muhammad (Muhammad ibn ʿAbdullāh), and a leader of the entire Muslim community. The Rashidun caliphs, who directly succeeded Muhammad as leaders of the Muslim community, were chosen through shura, a process of community consultation that some consider an early form of Islamic democracy. During the history of Islam after the Rashidun period, many Muslim states, almost all of them hereditary monarchies, have claimed to be caliphates. Even though Caliphates were thought to go back to Muhammad, they were not thought of as having the same prophetic power as he did.

Scholars debate what exactly constitutes an empire. Generally, they may define an empire as a state that extends dominion over areas and populations distinct culturally and ethnically from the culture/ethnicity at the center of power.