Casimir I of Oświęcim

Casimir I
Duke of Oświęcim, Toszek, Strzelin
Coat-of-arms of Upper Silesia (Opole, Oświęcim, Toszek, Strzelin, etc).
Born1396
Died7 April 1434
Noble familySilesian Piasts of Opole
Spouse(s)Anna of Żagań
Margareta of Opava-Ratibor
IssueWenceslaus I
Przemysław
Jan IV of Oświęcim
FatherPrzemysław of Oświęcim
Motherunknown

Casimir I of Oświęcim (Polish: Kazimierz I Oświęcimski) (1396 – 7 April 1434) was a Duke of Oświęcim from 1406 (under regency until 1414) until his death in 1434, ruler over Toszek (from 1414 to 1434) and Strzelin (during 1416–1427).

He was the only child of Duke Przemysław of Oświęcim by his unknown wife.