Maria, Queen of Hungary. She was born in Brussels to Philip I of Castile "The Handsome" and Joanna "The Mad" of Castile. Her paternal grandparents were Maximilian I, Holy Roman Emperor and his first wife Mary of Burgundy. Her maternal grandparents were Ferdinand II of Aragon and Isabella of Castile. She was the niece of Catherine of Aragon.
Filips de Schone en Joanna de Waanzinnige Joanna (6 November 1479 – 12 April 1555), known as Joanna the Mad (Spanish: Juana la Loca), was heiress of the Kingdoms of Castile and Aragon, a union which evolved into modern Spain.