Auxiliary Legion

The Auxiliary Legion, also called the British Legion (La Legión Británica) or Westminster Legion, existed from 1835 to 1837. It was a British military force sent to Spain to support the Liberals and Queen Isabella II of Spain against the Carlists in the First Carlist War.

Under the Quadruple Alliance, Great Britain had controlled maritime traffic along the Cantabrian coast since the beginning of the war.

In 1835 the war was not going well for the Liberal side and they asked their allies to become more involved in the war. The French sent their Foreign Legion which landed at Tarragona on 17 August with around 4,000 men and was renamed the Spanish Legion. Although the British refused to send troops directly, in June 1835, they decided to form a military volunteer corps, and that became designated an auxiliary to the Spanish Legion. The corps was to be funded and their soldiers paid by the Spanish crown.

By the end of the summer of 1836 a force of 10,000 men under the command of De Lacy Evans had assembled in San Sebastian. They fought near Hernani and Vitoria, but were pushed back and had to hold the fort on Mount Urgul de San Sebastian, to prevent the Carlists from taking the city.

In November 1836 they were put under the command of Baldomero Espartero and helped to lift the siege of Bilbao.

In 1837 the Legion suffered a serious defeat in the Battle of Oriamendi, but they led a successful offensive on the Carlist rearguard along the Biscay coast during the Expedición Real, an attempt by the Carlists main force to march on Madrid. During the offensive, Legion and Spanish loyalist forces managed to take over Irun.

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