Before adopting Islam a process that was greatly facilitated by the Abbasid victory at the 75 battle of Talas, which ensured Abbasid influence in Central Asia the Turkic peoples practiced a variety of shamanism. After this battle, many of the various Turkic tribes including the oguz 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. In the Ottoman Empire, in accordance with the Muslim Dhimmi system, Christians were guaranteed limited freedoms such as the right to worship but were treated as second class citizen. Christians and Jews were not considered equals to Muslims: testimony against Muslims by Christians and Jews was inadmissible in courts of law.