Muhammad received his first revelations in A.D. 610. Barely 100 years later, the Muslim empire dominated the Middle East, northern Africa, parts of Asia and into Europe. How Muslims achieved this lightning-fast conquest still vexes historians today, but they agree that it was a mix of conquest, cultural openness and the appeal of Islam itself.

The Spread of Islam Through Military Action

Persecuted in Mecca, Muhammad and his converts fled to Medina, where the new Muslims were welcomed. Muhammad dispatched raiding parties against Arabian tribes that did not accept Islam. His forces also fended off attacks from these non-believers. When Muhammad died in A.D. 632 his father-in-law Abu Bakr became “caliph,” which means “successor.” Abu Bakr began the Riddah Wars, to keep breakaway tribes in the Islamic fold. The next caliph, Umar, extended military actions to Syria and Palestine. By 650, Muslims conquered Egypt and North Africa. Less than 40 years later, they besieged Constantinople, and in 711 they pushed into Spain and India.

Islam Gains Acceptance by Tolerating Other Religions

Spain was ruled by Visigoths for more than 200 years. Jews suffered severe oppression under the Visigoths, but when Muslims arrived, Jews and Christians were allowed religious freedom. Muslims believed the God of the Jews and Christians was the same God worshipped by Muslims. The Jewish population of Spain offered no support to the Visigoths, who were quickly overrun by the Islamic conquerors. Jews and Christians participated in Muslim society economically and politically, paving the way for the Islamic empire to thrive. In Persia and Iraq, rather than suppressing pagan religious practices, Islam adapted them to fit the new religion, making conversion tolerable. Tax breaks for converts made Islam even more enticing.

Egalitarianism: Another Appealing Feature of Islam

Islam was an Arab religion but did not discriminate by ethnicity or race. In Muhammad’s original conception, all of mankind was equal under God’s law: people were judged only by how faithfully they followed Islamic law. Though this radical equality wasn’t fully realized in practice, with economic elites arising in the Islamic empire just like everywhere else, Islam’s egalitarian vision made it attractive to people who had previously been locked into rigid feudal systems that offered little hope to anyone outside local aristocracies.

Muslims Ruled Without Conquering

Tolerance and equality were not only Islamic ideals, they were pragmatic strategies. Muslims built their empire largely through force, but they were settlers, not conquerors. Muslim invaders didn’t interfere with the civilizations they subsumed, as long there was nothing that contradicted Islamic law. Islam offered itself not as a repudiation of earlier religions, but as a continuation. While other conquerors were interested in power and plunder, Muslim rulers understood that by incorporating and even aiding indigenous cultures, their own governments would remain more stable than if they were based on force alone. In that way, the Muslim empire not only spread, but endured and flourished for centuries.