Constantine XI Palaiologos
Helena was born in the castle of Mistras, Morea, Greece on 3 February 1428, the only child of Theodore II Palaiologos, Despot of Morea, and Cleofa Malatesta. Her paternal grandfather was Byzantine emperor Manuel II Palaiologos, and her uncles included emperors John VIII Palaiologos and Constantine XI Palaiologos. When she was five years old, her mother died. Her father never remarried as he was occupied in the war which was fought against the Latin states in Greece for the unification of Morea.