After the 10th century, Muslim Central Asian nomadic clans, using swift-horse cavalry and raising vast armies united by ethnicity and religion, repeatedly overran South Asia's north-western plains, leading eventually to the establishment of the Islamic Delhi Sultanate in 1206. The sultanate was to control much of North India and to make many forays into South India. Although at first disruptive for the Indian elites, the sultanate largely left its vast non-Muslim subject population to its own laws and customs. By repeatedly repulsing Mongol raiders in the 13th century, the sultanate saved India from the devastation visited on West and Central Asia, setting the scene for centuries of migration of fleeing soldiers, learned men, mystics, traders, artists, and artisans from that region into the subcontinent, thereby creating a syncretic Indo-Islamic culture in the north. The sultanate's raiding and weakening of the regional kingdoms of South India paved the way for the indigenous Vijayanagara Empire. Embracing a strong Shaivite tradition and building upon the military technology of the sultanate, the empire came to control much of peninsular India, and was to influence South Indian society for long afterwards.