In 610, while he was meditating near the city of Mecca, he began to experience a series of visions, in which God commanded the spread of monotheism to the polytheistic people of the Arabian peninsula. He also started writing the Koran, which is the holy book of Islam. Once he had gained followers in his faith, the rulers of Mecca began to view him as a threat to their rule. Finally, the authorities surrounded Muhammad and his followers in a corner of the city with the threat of letting them starve to death if Muhammad did not take back what he had taught/spread and his followers abandoned Muhammad and his monotheistic teachings.
At that time, two feuding factions around Medina became interested in Muhammad and his beliefs and invited him to come to their area. He fled (freed) from Mecca on 16 July 622 and left for the city of Medina. This date (the release of Muhammad) is called the Hijra, marking the beginning of Islam. After uniting with the ruler of Medina, Muhammad formed an army that was used to spread the Islamic faith to the next tribes. He again defeated Mecca in 630, and by the time of his death, his armies had converted most of the people of the Arabian peninsula.
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During the 10 years after Muhammad's death, the process of spreading Islam has reached Persia, Egypt, and throughout the Middle East. By the mid-eighth century, the areas controlled by the Islamic Empire both politically and religiously stretched from Spain through North Africa to the Middle East, and into Central Asia. Currently, Islam is the second most followed religion in the world, with more than 800 million adherents, or approximately 17 percent of the world's population. Like Judaism and Christianity, Islam is monotheism. Followers of Islam believe in One God, namely Allah.
The Islamic creed is: "There is no god but Allah, and Muhammad is Allah's Messenger".
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