Islam in the Ottoman Empire
Islam was the official religion of the Ottoman Empire. The highest position in Islam, "caliphate", was claimed by the sultan, after the defeat of the Mamluks which was established as Ottoman Caliphate. The Sultan was to be a devout Muslim and was given the literal authority of the Caliph. Additionally, Sunni clerics had tremendous influence over government and their authority was central to the regulation of the economy. Despite all this, the Sultan also had a right to decree, enforcing a code called Kanun (law) in Turkish. Additionally, there was a supreme clerical position called the Sheykhulislam ("Sheykh of Islam" in Arabic). Minorities, particularly Christians and Jews but also some others, were mandated to pay the jizya, the poll tax as mandated by traditional Islam.
Ottoman Crete
One result of the Ottoman conquest was that a sizeable proportion of the population gradually converted to Islam, with its tax and other civic advantages in the Ottoman system. Contemporary estimates vary, but on the eve of the Greek War of Independence as much as 45% of the population of the island may have been Muslim. A small number of these were crypto-Christians who converted back to Christianity; others fled Crete because of the unrest. By the last Ottoman census in 1881, Christians were 76% of the population, and Muslims (usually called "Turks" regardless of language, culture, and ancestry) only 24%, but Muslims were over 60% in the three large towns on the north coast and Monofatsi. Christians were 93% of the population in 1923 of the districts of Crete. The remaining Muslims were transferred to Turkey in the population exchange by religion between Greece and Turkey.