The Ottoman Dynasty (or the Imperial House of Osman) (Turkish: Osmanlı Hanedanı) ruled the Ottoman Empire from 1299 to 1922, beginning with Osman I (not counting his father, Ertuğrul), though the dynasty was not proclaimed until Orhan Bey declared himself sultan. Before that the tribe/dynasty might have been known as Söğüt but was renamed Osmanlı (Ottoman in English) in honour of Osman.
The sultan was the sole and absolute regent, head of state and head of government of the empire, at least officially, though often much power shifted de facto to other officials, especially the Grand Vizier. See the article on state organisation of the Ottoman Empire for further information on the sultan and the structure of power.
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