Islam is by far the most practiced religion in Turkey. Most Turkish people are Sunni Muslims, and most of them belong to the Hanafi school of jurisprudence. Smaller numbers belong to the Alevi, Ja'fari and Alawite minorities. The established presence of Islam in the region that now constitutes modern Turkey dates back to the second half of the 11th century, when the Seljuks started expanding into eastern Anatolia.