Alfonso VI of León and Castile
Sancho IV was assassinated in Peñalén (Funes), whence his nickname, by a conspiracy headed by his brother Ramón Garcés ("el Fratricida", the Fratricide) and his sister Ermesinda. During a scheduled hunt, Sancho was forced from a cliff by his siblings. Upon his assassination, the kingdom was invaded and ultimately partitioned between Sancho of Aragon and a third cousin, Alfonso VI of León and Castile. Alfonso occupied La Rioja and Sancho was proclaimed king in Pamplona.