The Mali Empire was a Mandinka empire founded by Sundiata Keita (r. 1230–1255) in circa 1230 and existed up to 1600. As detailed in the "Epic of Sundiata", Mali emerged as a breakaway region of the Sosso Empire, which itself had split from the earlier Ghana Empire. Thereafter Mali defeated the Sosso at the Battle of Kirina in 1235 and then Ghana in 1240. From its heartland around the modern Guinea-Mali border region, the empire expanded considerably under successive kings and came to dominate the Trans-Saharan trade routes, reaching its greatest extent during the rule of Mansa Musa (r. 1312–1337). At this point parts of what are now Niger's Tillabéri Region fell under Malian rule. A Muslim, Mansa Musa performed the "hajj" in 1324–25 and encouraged the spread of Islam in the empire, though it appears that most ordinary citizens continued to maintain their traditional animist beliefs instead of or alongside the new religion. The empire began declining in the 15th century due to a combination of internecine strife over the royal succession, weak kings, the shift of European trade routes to the coast, and rebellions in the empire's periphery by Mossi, Wolof, Tuareg and Songhai peoples. However a rump Mali kingdom continued to exist until late 1600s.