Thomais Orsini

Thomais Orsini (born ca. 1330) was the queen consort of the Serbian tsar and ruler of Epirus and Thessaly, Simeon Uroš Palaiologos.

Born Thomais Komnene Angelina in the early 1330s, she lost her father John II Orsini in 1335, when he was poisoned, allegedly by his wife, Anna Palaiologina, a scion of the ruling Palaiologos dynasty of the Byzantine Empire. After John II's death, his wife Anna became regent of the Despotate of Epirus for Thomais' brother, Nikephoros II.

Soon, however, in 1338, the Orsini were evicted from Epirus by the Byzantine emperor Andronikos III Palaiologos, who annexed Epirus to the Byzantine Empire. Nevertheless, during the destructive Byzantine civil war that followed Andronikos III's death in 1341, most of the remaining Byzantine territories, including Epirus and Thessaly, fell to the forces of the Serbian ruler Stephen IV Dušan, who in 1346 founded the Serbian Empire. In 1348, Dušan appointed his younger half-brother, the half-Greek Simeon Uroš Palaiologos, as governor of Acarnania and the southern parts of Epirus.

To consolidate his position with the local population, Simeon decided to marry Thomais, the descendant of the former ruling Epirote line. Together they had three children: John Uroš, who succeeded as ruler of Thessaly, Stephen Uroš, governor of Pharsalos, and Maria, who married Thomas II Preljubović, who also ruled over Epirus.

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