War of the Bands

The War of the Bands (Basque: Bando gerrak, Spanish: Guerra de los Bandos) was a civil war, really an extended series of blood feuds, in the western Basque Country, Gascony, and Navarre in the Late Middle Ages. The main primary source for the War is Las Bienandanças e fortunas by Lope García de Salazar, written c.1471. The war is named after the aristocratic networks of familial alliances and their armed followings, known as bandos (bands), that carried out constant wars for power and honour across three kingdoms. The wars ceased only with the imposition of royal authority under Ferdinand II of Aragon and Isabella of Castile, the Catholic Monarchs.

The wars resulted partly from the destabilising effect of the Castilian Civil War and the ensuing political weakness of the House of Trastámara. That the Seniory of Biscay effectively ceased to exist after 1370 and was subsumed in 1379 into Castile only exacerbated the effects of political anarchy on Biscay. The rise of the towns, notably Bilbao and Bermeo, caused jockeying for municipal power between the rich urban families. The landed nobility, enfeoffed in the heavily encastellated countryside, nursed feuds that dated back centuries. The Ligizamon and Zamudiano had been enemies since 1270. Many minor noble families were caught in the feuds of the great families by ties of marriage.

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