Manuel II Palaiologos
Konstantin had married his daughter Jelena to the Byzantine Emperor Manuel II Palaiologos (r. 1391-1425), from which the last Byzantine Emperors John VIII (r. 1425-1448) and Constantine XI (r. 1449-1453) sprung. Constantine XI, who died defending Constantinople from the Ottomans in 1453, was known by his mother's surname, in Greek, Dragases (Δραγάσης, "Dragáses").