Theodora Kantakouzene was a Byzantine princess, the daughter of Emperor John VI Kantakouzenos and the fifth wife of the Ottoman Sultan Orhan Gazi.
Background
In January 1346, to cement her father"s alliance with the rising Ottoman emirate and to prevent the Ottomans from giving their aid to the Empress-regent Anna of Savoy during the ongoing civil war, she was betrothed to the Ottoman ruler, Orhan Gazi.
Career
The historian Nikephoros Gregoras erroneously calls her "Maria" in one passage. The marriage took place in the summer of the same year. A ceremony was held at Selymbria, where Orhan"s envoys received her and escorted her to the Ottoman lands in Bithynia, across the Marmara Sea, where the actual wedding took place.
The Byzantine emperor John V Palaiologos was instrumental in his eventual release.
Later, Halil married Irene, a daughter of John V Palaiologos and Theodora"s sister, Helena Kantakouzene. Except for a three-day sojourn in Constantinople in February 1347, in the aftermath of her father"s victory in the civil war, Theodora remained at the Ottoman court until Orhan"s death in 1362.
She is last known to have been held imprisoned at Galata during the brief reign of Andronikos IV Palaiologos there in 1379-1381.