John VIII, Palaiologos

John VIII Palaiologos or Palaeologus (Greek: Ἰωάννης Παλαιολόγος, romanized: Iōánnēs Palaiológos; 18 December 1392 – 31 October 1448) was the penultimate Byzantine emperor, ruling from 1425 to 1448. As the eldest son of Manuel II Palaiologos and Helena Dragaš, he was co-emperor with his father before 1416 and took sole control in 1425. During his rule, he defended Constantinople from a siege by Murad II but conceded the loss of Thessalonica. To secure protection against the Ottomans, he visited Italy twice and consented to the union of the Greek and Roman churches, a move which was ultimately unsuccessful due to opposition in Constantinople. Before his death in 1448, John VIII named his brother Constantine XI as his successor. He was married three times but had no children. Notably, John VIII was the last reigning Byzantine emperor to die of natural causes and was depicted by several painters during his visit to Italy.