Theodore Spandounes (Greek: Θεόδωρος Σπανδούνης, Italian: Teodoro Spandugino) was an early 16th-century Greek historian of noble Byzantine extraction; the son of exiles fleeing the Ottoman conquest of Byzantium who had settled in Venice, Italy. As a youth he stayed with relatives in Ottoman-ruled Macedonia and visited the Ottoman capital at Constantinople, acquiring a knowledge of their history and culture. In later life he served successive Popes as a counsellor and repeatedly advocated the dispatch of a new Crusade against the Ottomans. His chief legacy is his Italian-language history on the origins of the Ottoman state and its history up to that time, whose first version was published in 1509 in Italian and was soon translated into French. Spandounes continued working on it, with the final version appearing in 1538. The work is disorganized and contains errors, but is extremely valuable as a historical source for its wealth of information.