Mary of Bytom

Maria of Bytom
The funeral of Maria of Bytom, miniature from the Chronicon Pictum.
Queen consort of Hungary
Tenure	1306–1317
Born	before 1295
Died	15 December 1317 (aged 22) Temesvár, Hungary
Burial	Székesfehérvár Basilica
Spouse	Charles I of Hungary
Issue	Catherine, Duchess of Świdnica? Elisabeth, Duchess of Niemodlin?
House	House of Piast (by birth) House of Anjou (by marriage)
Father	Casimir of Bytom
Mother	Helena
Religion	Roman Catholic

Maria of Bytom (Polish: Maria bytomska; before 1295 – Temesvár (Timişoara), Kingdom of Hungary, 15 December 1317), was a Polish princess member of the House of Piast in the Bytom branch and by marriage Queen of Hungary.

She was the third child and only daughter of Duke Casimir of Bytom by his wife Helena, whose origins are unknown, although the later historiography tends to recognize her as a daughter of Lev I of Galicia, from the Rurikid dynasty.

Maria was the first or second wife of Charles I Robert of Anjou, King of Hungary. This union was childless, but older literature claimed that they had two daughters. Little is known about the activities of Mary as Queen of Hungary. Her marriage to Charles I Robert consolidated the Polish-Hungarian agreement directed against the Kingdom of Bohemia, and also helped to establish a close Polish-Hungarian relations in the 14th century, reflected in the ecclesiastical career in Hungary of Maria's brothers, Bolesław and Mieszko, and the later third marriage of Charles I Robert with Elizabeth of Kujavia.

The exact date of birth of Maria is unknown. In 1306, when she was married to Charles Robert, contemporary Canon Law established that the minimal age for marriage must be at least 12 years old; thus, she was born in 1294 at the latest. She was the first member of the Silesian branch of the Piast dynasty named Maria; reasons for this suggestion of name are also unknown. Among the children of Casimir of Bytom she was usually placed in the sixth and last place, but she could even be born as the third child, in turn.