Berengaria, nicknamed the Great, was Queen of Castile for a brief time in 1217, and Queen of León from 1197 to 1204 as the second wife of King Alfonso IX. As the eldest child and heiress presumptive of Alfonso VIII of Castile, she was a sought after bride, and was engaged to Conrad, the son of Holy Roman Emperor Frederick I. After Conrad's death, she married her cousin Alfonso IX of León to secure the peace between him and her father. She had five children with him before their marriage was voided by Pope Innocent III.

Alfonso IX was King of León and Galicia from the death of his father Ferdinand II in 1188 until his own death.