John VIII Palaiologos or Palaeologus was the penultimate Byzantine emperor. Ruling from 1425 to 1448, he attempted, and failed, to bring about the reunification of the Orthodox and Catholic churches and prioritized the protection of Constantinople against the Ottoman Empire. He was succeeded by his brother, Constantine XI.
Portrait of John VIII Palaiologos from a manuscript at Saint Catherine's Monastery c. 1440
Medal of the Emperor John VIII Palaiologos during his visit to Florence, by Pisanello (1438). The legend reads, in Greek: "John the Palaiologos, basileus and autokrator of the Romans".
Sketches of John VIII Palaiologos during his visit at the Council of Florence in 1438, by Pisanello
Constantine XI Dragases Palaiologos or Dragaš Palaeologus was the last Roman (Byzantine) emperor, reigning from 1449 until his death in battle at the Fall of Constantinople in 1453. Constantine's death marked the definitive end of the Eastern Roman Empire, which traced its origin to Constantine the Great's foundation of Constantinople as the Roman Empire's new capital in 330.
Ruins of the castle at Patras, captured by Constantine in 1430
Contemporary sketches by Pisanello of the Byzantine delegation at the Council of Florence. The figure mounted on the horse is Constantine's brother, Emperor John VIII Palaiologos.
The Despot's Palace in Mystras, from which Constantine ruled as Despot of the Morea 1443–1449