Date of Birth: 
About Stanisław of Masovia
- Stanislaw of Masovia (pl: Stanislaw mazowiecki; 17 May 1501 – 8 August 1524), was a Polish prince member of the House of Piast in the Masovian branch.
- He was a Duke of Czersk, Warsaw, Liw, Zakroczym and Nur during 1503-1524 (under regency until 1518) jointly with his brother. He was the eldest son of Konrad III the Red and his third wife Anna, a daughter of Mikolaj Radziwill the Old, Voivod of Vilnius and the first Grand Chancellor of Lithuania.
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