Gonzalo Menéndez

In 966, Gonzalo assassinated Sancho I of León. He invited him to a banquet and fed him poisoned food, an apple according to some sources.[2] In the late 960s Gonzalo's lands came under the ravages of the Vikings. In 968, he fell out with king Ramiro III after the latter refused to fight them. In the factional and successional politics of the time, Gonzalo may be said to have favoured the line of Ordoño III and his son Vermudo II over Sancho I and his son Ramiro III.

A dispute between Gonzalo's mother, abbess of Guimarães in her widowhood, and a relative of the Galician magnate Rodrigo Velásquez, spurred a rivalry between the two families that would span several years. Rodrigo's brother's sister-in-law, Guntroda, abbess of Pazóo, had appropriated the monastery of Santa Comba, which belonged to a monk name Odoino, who appealed to Mummadomna for support. She sent her sons Gonzalo and Ramiro to force Guntroda to return it volens nolens (willing or not). The conflict left to open warfare between the factions led by Gonzalo and Rodrigo. In 968 or perhaps 974, Gonzalo defeated his rival in the Battle of Aguioncha.

Justo Pérez de Urbel argued that the absence of Rodrigo and Gonzalo from court during the regency of queen Elvira Ramírez was evidence that during this period they were de facto independent, but they were in León on 20 September 968 for the confirmation of a noble gift to the abbey of Sobrado.[3]

In 981, after the Christian defeat at the Battle of Rueda, he led the rebellion against Ramiro III that installed the king's cousin Ordoño Bermúdez, perhaps Gonzalo's nephew, on the throne.[4] Gonzalo was soon joined by his son Menendo González, and by Tedón Aldretiz, Tello Eloritiz, Gutier Díaz, Rodrigo Sarracínez, Gonzalo Álvarez, and Gonzalo Díaz. Among the bishops to support the revolt were Viliulfo of Coimbra, Ikilano of Viseu, and James of Lamego. The first document which titles Vermudo "king" (Vermudus rex, prolix domni Ordoni)[5] is a donation to the monastery of Lorvão of the fourth part of the villages of Palos and Lamas made by Gonzalo on 22 December that year. Vermudo had signed a document with his cousin on 11 October, and the success of the rebellion must have come after that date. Gonzalo is sometimes credited with chasing Pelayo Rodríguez, the son of his old enemy Rodrigo Velázquez, from the diocese of Iria Flavia in the fall of 982, for Vermudo's coronation.[6]

In 985 Gonzalo—and many other Portuguese magnates—had begun to employ the title duke (dux); Gonzalo is usually listed on documents ahead of all of them.[7] In 994 he was granted the city and territory of Braga. He was killed in 997 during Almanzor's campaign against Santiago de Compostela.