Katarzyna Telniczanka (1480–1528), was a Polish noble. She was the royal mistress of king Sigismund I the Old, and the mother of three children by the monarch.[1][2]
Katarzyna, who was reputedly not of noble birth, may have taken her surname from her place of origin - the village of Ternice in Moravia.[3][4] However, her original family name may have been Ochstat.[5][6] She became the mistress of the king c. 1498.
She was the mother of John of the Lithuanian Dukes, future bishop of Poznań (8 January 1499 – 18 February 1538), Regina (1500/1 – 20 May 1526), wed c. 20 October 1518 Hieronim Szafraniec, Starost of Cieszyn (d. 1556/59), and Katarzyna (1503 – before 9 September 1548), wed after 1522 George II Count von Montfort in Pfannberg (d. 1544).
In 1509, she married the nobleman Andrzej Kościelecki.[7] She had one child while married, Beata Łaska z Kościeleckich, who was reputed to be the child of the Sigismund as well.[2]
She followed her son John to his position in Lithuania, where she had great influence in his court.