What issue initially created a source of contention and division for Muslims into Sunni and Shi’a?

After Muhammad’s death, Muslims disagreed about who should lead the community. Sunnis generally supported choosing a leader from the community, while Shi’a held that leadership should pass through Muhammad’s family, beginning with Ali. This disagreement over the right to leadership created the initial division; the issue was not the choice of a capital or whether Islam was monotheistic.

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