Islam began in Mecca in the early 7th century, with the teachings of the prophet Muhammad. It quickly spread throughout the Arabian Peninsula and, by the middle of the 7th century, had reached as far as North Africa and Persia. Within a century of Muhammad's death, Islam had spread to Spain, Central Asia, China, and India. The main factors that contributed to the spread of Islam were its simplicity, its message of social justice, and its military conquests.