born June 18, 1332, Didymoteichon
died Feb. 16, 1391, Constantinople
Byzantine emperor (1341–91).
The son of Andronicus III Palaeologus , he inherited the throne at age nine; John VI Cantacuzenus served as his regent and coemperor (1347–54). After the Ottoman Turks gained control of Galliopoli and threatened Constantinople, John V appealed to the West for help, proposing to end the schism between the Byzantine and Latin churches. Impoverished by war, he was detained as a debtor when he visited Venice (1369). In 1371 he was forced to recognize Turkish overlords, who later helped him to regain the throne (1379) after he was deposed by his son.