Both Khagan as such and the Turkish form Hakan, with the specification in Arabic "al-Barrayn wa al-Bahrayn" (meaning literally "of both lands and both seas"), or rather fully in Ottoman Turkish "Hakan ül-Berreyn vel-Bahreyn", were among the titles in the official full style of the Great Sultan (and later Caliph) of the Ottoman Empire, reflecting the historical legitimation of the dynasty's rule as political successor to various conquered (often Islamised) states.