State organisation of the Ottoman Empire

The Ottoman Empire developed over the centuries a complex organization of government with the Sultan as the supreme ruler of a centralized government that had an effective control of its provinces, officials and inhabitants. Wealth and rank could be inherited but were just as often earned. Positions were perceived as titles such as viziers and aghas. Military service was a key to advancement in the hierarchy.

The expansion of the Empire called for a systematic administrative organization that developed into a dual system of military ("Central Government") and civil administration ("Provincial System") developed a kind of separation of powers with most higher executive functions carried out by the military authorities and judicial and basic administration carried out by civil authorities. Outside this system were various types of vassal and tributary states. Most of the areas ruled by the Ottomans were explicitly mentioned in the official full style of the sultan, including various lofty titles adopted to emphasize imperial rank and show the empire as being "successor-in-law" to conquered states.

The empire was divided into vilayets, with a governor assigned to each vilayet. The idea of vilayet originated from the Seljuk vassal state (Uç Beyliği) in central Anatolia. Over the years the Empire became an amalgamation of pre-existing polities, the Anatolian beyliks, brought under the sway of the ruling House of Osman.

The central government was composed of the Sultan and his own staff (bookkeepers, etc.) in what was known as "House of Osman". The House of Osman was advised by the Divan, composed of the Grand Vizier and the ruling class (nobles). The ruling class was called the askeri, including the noblemen, court officials, military officers and the religious class called the ulema.

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