The family legend states that a noble named Rodrigo González de Cisneros saved the life of King Alfonso VI of León by giving the king his horse and thus allowing him to escape what was apparently a battle lost to a Moorish Kingdom. He cut three pieces (jirones or girones, in Spanish) from the King's tunic and later asked the King to allow him to use these in his coat of arms.
This legend has no foundations and the events are not mentioned by historians or in popular tradition. Most importantly, the use of coats of arms was unknown at the time of King Alfonso VI and it was not until a century later that this custom became common.[2]
In 1274, he gained ownership over the charter of Montiel and the towns of Cózar and Alcubillas. In 1275, he was elected as Grand Master of the Order of Santiago, succeeding Pelayo Pérez Correa. In that same here, Gonzalo was granted a lifelong title over areas in Montiel and was responsible for the repopulation, and the foundation of new localities.
Death
In 1280, Gonzalo died as a result of injuries received during the Battle of Moclín, which was fought on the 23rd of June of that year in the municipality of Moclín in Granada. More than 2,800 men died in that battle, including a large number of the members of the Order of Santiago. He was buried in the town of Alcaudete in Jaén.[4]
^Barón Faraldo, Andrés (2006). Grupos y dominios aristocráticos en la Tierrade Campos oriental, Siglos X-XIII (in Spanish). Palencia: Monografías. p. 171. ISBN84-8173-122-6.
de Salazar y Acha, Jaime (1989). "Los descendientes del conde Ero Fernández, fundador de Monasterio de Santa María de Ferreira de Pallares". El Museo de Pontevedra. No. 43. pp. 67–86. ISSN0210-7791.