John Zápolya
Beatrice was a daughter of Bernardin Frankopan, Knez (Prince) of Krk and Modruš (1453–1529) from his marriage to Donna Luisa Marzano d'Aragona, daughter of Giovanni Francesco Marino Marzano, Prince of Squillace. Her brother Christoph Frankopan (1482–1527) was Ban (Viceroy) of Croatia under the reign of the Hungarian king John Zápolya.