Islam spread from its birthplace in the Arabian Peninsula to Africa. Sundiata Keita (c. 1217 - c. 1255), the founder of the Mali Empire (which encompassed part of present-day Guinea as well as other modern nations), was not a Muslim, but by 1300, his successors were. The tenth ruler of the empire, Musa I (c. 1280 - c. 1337), made it the state religion.