Constantine XI Palaiologos
According to one of the many Greek legends about the Constantinople's fall to the Ottomans, when the Turks entered the city, an angel rescued the emperor Constantine XI Palaiologos, turned him into marble and placed him in a cave under the earth near the Golden Gate, where he waits to be brought to life again to conquer the city back for Christians. The legend explained the later walling up of the gate as a Turkish precaution against this prophecy.