She was the daughter of Ferdinand I of Aragon and Eleanor of Alburquerque.

Maria was married by her brother in his ambition to place his father's issue on the thrones of Castile and Aragon.

Maria was occasionally politically active on behalf of her brothers, the princes of Aragon; she disregarded her husband's policy in favor of her brothers and the relationship between Maria and John was somewhat tense.

Maria has no descendants today, her line having gone extinct within a few decades of her death.

Maria and John II of Castile had four children: