The Despotate of Epirus was one of the late Byzantine successor states of the Byzantine Empire established in the aftermath of the Fourth Crusade in 1204 by a (matrilineally linked) branch of the Doukas noble clan. It claimed to be the legitimate successor of the Byzantine Empire, along with the Empire of Nicaea and the Empire of Trebizond. Conquered by the Serbian Kingdom in 1337, it was restored in 1356 and existed until the Ottoman conquest in 1479. The Despotate was centred on the province of Epirus in Albania and northwestern Greece and the western portion of Greek Macedonia and also included a small strip of Thessaly and western Greece as far south as Nafpaktos. Through a policy of aggressive expansion under Theodore Komnenos Doukas the Despotate of Epirus also briefly came to incorporate central Macedonia, with the establishment of the Empire of Thessalonica in 1224, and Thrace as far east as Didymoteicho and Adrianopolis.