The birth of Islam, the youngest of the three Abrahamic religions, began in 610 with the revelation of the Qur’an (also spelled Koran) to Muhammad in a cave outside the Arabian city of Mecca. Driven by dissatisfaction with the religious life of his family and fellow citizens, the merchant Muhammad had retreated into the wilderness to build up his spiritual inner life through mystical contemplation. After years of this discipline, observed periodically for days or weeks at a time, something he had never expected happened: The archangel Gabriel began to dictate to him a scripture written by God, the new revelation of the Qur’an. The example of Muhammad’s faith in his new revelation inspired his family and friends, who persuaded him, against his own reluctance, to begin to preach on the street corners of Mecca. His opposition to the traditional polytheist religion practiced in common by the whole city caused him and his followers to be exiled from Mecca, an event called the Hijra. But through skillful diplomacy and conquest, Muhammad became the ruler of the entire Arabian Peninsula by the time of his death in 632, and almost the whole population of his realm converted to Islam, the new faith in the Qur’an—the book that was gradually revealed to Muhammad throughout this lifetime.