Constantine XI Palaiologos
Helena Palaiologina, born 23 April 1442, was the daughter and only child of Demetrios Palaiologos, Despot of the Morea, a brother of Constantine XI Palaiologos, the final Byzantine emperor. Her mother was Theodora Asanina, the daughter of Paul Asan, part of the ancient Asen family, which had once ruled the Second Bulgarian Empire. At the time of Helena's birth, Demetrios was the Despot of Mesembria, not being appointed as the Despot of the Morea until 1449. In her time, Helena was famous for being beautiful and high-spirited.