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.
Rise of the Ottoman Empire
Osman was adept at forging political and commercial relationships with nearby groups, Muslim as well as Christian. Early on he attracted several notable figures to his side, including Köse Mihal, a Byzantine village headman whose descendants (known as the Mihaloğulları) enjoyed primacy among the frontier warriors in Ottoman service. Köse Mihal was noteworthy for having been a Christian Greek; while he eventually converted to Islam, his prominent historical role indicates Osman's willingness to cooperate with non-Muslims and incorporate them into his political enterprise.