John V Palaeologus
His reign was marked by the gradual dissolution of the Empire. In his reign, the Ottomans took Adrianople and Philippolis, conquered Serbia and exacted tribute from the emperor. After the Ottoman Turks gained control of Gallipoli and threatened Constantinople, John V appealed to the West for help, proposing to end the schism between the Byzantine and Latin churches by submitting to the supremacy of the Roman Church. Impoverished by war, he was detained as a debtor when he visited Venice (1369). In 1371 he recognized the suzerainty of the Ottoman sultan Murad I, who later helped him to regain the throne (1379) after he was deposed by his son Andronicus IV in 1376. In 1390 his grandson, John VII Palaeologus, briefly usurped the throne. John V was succeeded by his son Manuel II Palaeologus. To his second son Theodore I Palaeologus he gave the Despotate of Morea in 1383.
In the end 1390 emperor ordered the restoration of the Constantinople Golden Gate using for this work marble from decayed churches of city. Upon termination of works, Beyazid I, demanded of him to tear them down. John V obeyed the sultan's order, but could not bear such humiliation and died of a stroke on February 16, 1391.