Siemowit III, Duke of Masovia

Polish nobleman (1314–1381)

Parents

• Maria of Galicia
• Trojden I, Duke of Masovia

Children

• Janusz I of Warsaw
• Margaret of Masovia
• Henry of Masovia
• Stanisław Siemowit of Masovia
• Siemowit IV
• Euphemia of Masovia

Siblings

• Casimir of Masovia
• Bolesław Jerzy of Mazovia
• Eufemia of Masovia

Partners

• Euphemia of Opava
• Anna von Münsterberg