Battle of Andoain

Battle context

The Battle of Andoain, fought near the Basque village of the same name south of San Sebastián, was part of the ongoing Liberal effort to consolidate control in the Basque Country during the First Carlist War. Liberal forces under Leopoldo O'Donnell had seized Andoain on 9 September 1837, pushing the Carlist garrison across the Oria River. The subsequent Carlist counterattack, reinforced by troops from Navarre under José Ignacio de Uranga, tested Liberal forward positions in a strategically sensitive zone close to their principal stronghold at San Sebastián. Liberal casualties ranging between 100 and 750 against a numerically inferior Carlist force of roughly 3,000 suggest the counteroffensive was effective, reflecting the persistent Carlist capacity to contest Liberal advances in the northern theatre despite overall manpower disadvantages.