Students of Muslim history often tend to conflate the Arab conquests with the spread of Islam when, in fact, the two events are distinct historical processes separated by centuries. During the first century after the Hijrah, rapid expansion of Muslim territory occurred under the impetus of military campaigns. However, these lands did not at that time suddenly become "Islamic." The spread of Islam among the population of these lands was a gradual process that continued for centuries, even in the regions conquered in the seventh century.

The chronology below traces major milestones in the expansion of Islam. It marks both dates when various regions became exposed to Islam, and also gives a range of dates within which Muslims likely became a majority of the population in those areas.

750s: Muslim soldiers settle in Chang'an (Xian) while Muslim merchants regularly visit and...