Mieszko I, Duke of Teschen

Mieszko I of Cieszyn (Polish: Mieszko cieszyński, Czech: Měšek I. Těšínský, German: Mesko I (Teschen); also known as Mieszko I of Opole

1252/56 – by 27 June 1315), was a Duke of Racibórz during 1282–1290 (with his brother as co-ruler) and the first Duke of Cieszyn since 1290 until his death.

He was the oldest son of Władysław, Duke of Opole-Racibórz, by his wife Euphemia, daughter of Władysław Odonic, Duke of Greater Poland.

Little is known about the early years of Mieszko I's life. His first documented mention was on 21 October 1258, when he appears together with his father and two younger brothers in the consent of the foundation of a Cistercian abbey in Rudy.

After his father's death in 1282, and according to the custom during the fragmentation of Poland, Mieszko and his brothers divided the Duchy of Opole-Racibórz between them: Mieszko and his youngest brother Przemysław received together the district of Racibórz as co-rulers. The other two brothers, Casimir and Bolko I, received Opole. Because Przemysław was still a minor a that time, Mieszko ruled alone until he attained his majority, in 1284.

In 1285 Mieszko politically supported the Bishop of Wrocław, Thomas II Zaremba against Henry IV Probus, providing shelter to the Bishop in Raciborz. His politics against Henry IV were reinforced when the Duke of Wrocław repudiated his wife Constance —sister of Mieszko— and sent her back to her homeland. Another consequence of Mieszko's politics was an armed expedition of Henry IV in 1287 against Racibórz, who was sieged. Then Mieszko was forced to refuse his help to the Bishop.

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