Venerable Hypomone, the Empress Helen Dragas, mother of the last Emperor of Constantinople.
Helen Dragas, a Serbian princess, married the Emperor Manuel II Palaiologos and was the mother of the last two emperors, John VIII and Constantine XI. After her husband's death she became a nun with the name Hypomone, meaning patience, and devoted herself to prayer and charity.
She reposed in 1450, three years before the fall of the City, and her relics are venerated at the Monastery of Saint Patapios near Loutraki.
Feast day
On the New Calendar, Hypomone the Righteous is commemorated on May 29. Churches on the Old (Julian) Calendar keep the feast on June 11 of the civil calendar.
Who celebrates a name day
People with these names keep their name day on this feast:
Ypomoni, Hypomone, Ipomoni, Ypomeni
Also commemorated on May 29

Theodosia of Tyre
Holy Woman, Θεοδοσία η Παρθένος
Virgin Martyr Theodosia of Tyre, drowned at Caesarea for her faith.
Alexander of Alexandria
Hierarch, Αλέξανδρος Αλεξανδρείας
Saint Alexander, Patriarch of Alexandria, who first condemned Arius.
Fall of Constantinople
Saint, Άλωσις της Κωνσταντινουπόλεως
Memorial of the fall of Constantinople to the Ottoman Turks in 1453.
John Nannos of Thessalonica
Martyr, Ιωάννης ο Νάννος
New Martyr John Nannos of Thessalonica, beheaded at Smyrna.
Andreas Argentis
Martyr, Ανδρέας ο Αργέντης
New Martyr Andreas Argentis of Chios, beheaded in Constantinople.