THE BATTLE OF ELORRIO
Elorrio was granted its founding charter as a town in 1356
by Don Tello, Lord of Bizkaia.
The charter and the laws that went with it were granted for two purposes: to defend Bizkaia against the continual attacks that it was suffering from Gipuzkoa as part of the ongoing power struggle between noble families, and to establish a municipal seat of power to balance the power of the rural lords.
It was on 21st of February 1468, over a century later, when that same power struggle erupted into the Battle of Elorrio.
The Battle of Elorrio was fought between the house of Ibarra, which supported the Oñacino faction, and that of Marzana, which favoured the opposing Gamboino faction. Fighting beside the Ibarras were the Muxica, Butrón, Arteaga, Salazar and Zarate families, while with the Marzanas stood the Avendaño family and their allies Sancho and Luis de Velasco, the counts of Saliñas and Haro, Juan de Briviesca and 300 Castilian mercenaries hired by the Marquess of Santillana.
It is considered as one of the great battles of the Middle Ages. In his account Bien Andanzas y Fortunas the chronicler Lope García de Salazar states that thousands of men took part. It was also one of the first battles in which the destructive force of artillery was seen. Up to that time it had been relatively ineffective, causing more noise than actual damage. The Duranguesado district, and indeed the rest of the Seigneury of Bizkaia, became a frequent battleground.
The bloody Battle of Elorrio ended with a crushing victory for the house of Marzana and its allies from the Gamboino faction, who were also aided by the townspeople of Elorrio itself. The Salazars fought in the battle on the Oñacino side. According to García de Salazar several thousand men from the lineages of Salazar, Butrón and Muxica were killed, including three of his own sons.