Turkic peoples practised a variety of shamanism before adopting Islam. Abbasid influence in Central Asia was ensured through a process that was greatly facilitated by the Muslim conquest of Transoxiana. Many of the various Turkic tribes—including the Oghuz Turks, who were the ancestors of both the Seljuks and the Ottomans—gradually converted to Islam, and brought the religion with them to Anatolia beginning in the 11th century. Since the founding of the Ottoman Empire, the Ottomans followed the Maturidi creed (school of Islamic theology) and the Hanafi madhab (school of Islamic jurisprudence).