Islam spread through military conquest, trade, pilgrimage, and missionaries. Arab Muslim forces conquered vast territories and built imperial structures over time. ... The caliphate—a new Islamic political structure—evolved and became more sophisticated during the Umayyad and Abbasid caliphates.

What kind of diffusion is Islam?

Islam spread mostly through contagious diffusion by military conquest into North Africa and Western Europe and through Arab traders traveling to Indonesia. Buddhism spread primarily through relocation diffusion by missionaries and was slow to diffuse outside the area of origin.

How did Islam spread so rapidly?

The religion of Islam spread rapidly in the 7th century. Islam spread quickly because of the military. During this time, on numerous accounts there were military raids. Trade and conflict were also apparent between different empires, all of which resulted in the spreading of Islam.