Katharina of Poland, Countess of Montfort German countess (1503–1548) Parents Katarzyna Telniczanka Sigismund I the Old Children Franziska of Montfort-Peggau, Countess of Manderscheid Jacob, Count of Montfort-Peggau Siblings Beata Kościelecka Wojciech Olbracht John Jagiellon Sigismund II Augustus Hedwig Jagiellon, Electress of Brandenburg Isabella Jagiellon Sophia Jagiellon, Duchess of Brunswick-Lüneburg Anna Jagiellon Anna Jagiellon Catherine Jagellon Regina Szafraniec Partners George, Count of Montfort-Pfannberg