In politics, he unified several Arab tribes, which allowed the Arab conquests of what would become a caliphate that stretched from Persia to the Iberian Peninsula.
To create the Islamic religion, he criticized one of Mecca's greatest sources of income: the pilgrimage of the idolaters, who worshiped the various deities of the local temples. Muhammad began preaching the belief in one god, Allah, and gathered his messages in a holy book for the Muslims, the Koran. Persecuted in Mecca, the Prophet and his followers fled to create the first Islamic community in Medina, a nearby oasis. This forced migration, known as Hijrah, marks the beginning of the Muslim calendar. Gradually, the prophet attracted more and more followers until he had the strength to defeat the rivals that expelled him from Mecca.
Using as a doctrine the new religion - which assimilated Jewish traditions, combined with Christian concepts and ideals of the Arab tribes - he managed to unify all of Arabia under his leadership.