Siemowit I of Masovia

Polish duke (1215–1262)

Parents

• Agafia of Rus
• Konrad I of Masovia

Children

• Konrad II of Masovia
• Bolesław II of Masovia

Siblings

• Judith of Masovia
• Casimir I of Kuyavia
• Bolesław I of Masovia
• Eudoxia of Masovia
• Dubrawka of Masovia

Partners

• Pereiaslawa of Galicia