Helena Kantakouzene

Helena Kantakouzene (1333–1396), a daughter of Emperor John VI Kantakouzenos, was the empress of John V Palaiologos. Her marriage in May 1347, when she was about thirteen, sealed the settlement ending the civil war of 1341–1347 and made her father senior co-emperor over her husband.

The peace held until 1352, when war with her father resumed. When her son Andronikos IV deposed John V in 1376, she failed to reconcile them, and after John V escaped prison in 1379 she was suspected: Andronikos held her, her aged father and her sisters hostage at Galata until the treaty of May 1381.

After John V died in 1391 she became the nun Hypomone, and in 1393 she was regent for Manuel II. She died in 1396.