who was andreas palaiologos?
He was recognized as the titular Despot of the Morea.
Andreas Palaiologos
Andreas Palaiologos or Palaeologus (; 17 January 1453 – June 1502), sometimes anglicized to Andrew, was the eldest son of Thomas Palaiologos, Despot of the Morea. Thomas was a brother of Constantine XI Palaiologos, the final Byzantine emperor. After his father's death in 1465, Andreas was recognized as the titular Despot of the Morea and from 1483 onwards, he also claimed the title "Emperor of Constantinople" ().

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Andreas Palaiologos [SEP] Introduction
Andreas traveled around Europe several times in search of a ruler who could aid him in retaking Constantinople, but rallied little support. The Ottoman Sultan Mehmed II, who had conquered Constantinople in 1453, died in 1481, and his two sons Cem and Bayezid fought a civil war over who would succeed him. Seeing his opportunity, Andreas attempted to organize an expedition in southern Italy during the summer of 1481 to cross the Adriatic Sea and restore the Byzantine Empire. The excursion was canceled in the autumn after Bayezid had successfully stabilized his rule. Although Andreas maintained hope of recapturing at least the Morea throughout his life, he never returned to Greece.