The Army of Galicia (in Spanish, Ejército de Galicia) was a Spanish military unit that took part in the Peninsular War against Napoleon’s French Grande Armée.
Created by the Supreme Junta towards the end of June 1808 to hold the Spanish left wing along the Cantabrian mountains against Napoleon's forces, it had a paper force of 43,000 regulars. Command was first given to General Blake, and then, in November 1808, to General La Romana.
Following the defeat of General Gregorio García de la Cuesta’s small and inexperienced Army of Castile at the Battle of Cabezón, which had forced Cuesta to abandon his seat of command at Valladolid to General Lasalle and escape to Benavente, Blake was ordered to combine the troops of his newly formed army with what was left of Cuesta’s forces. Blake had initially turned down a request to do so as the troops were still undergoing training and far short of their full numbers. Setting off with 27,000 foot soldiers and 150 cavalrymen, and after having left troops at different garrisons along the way, especially to guard the gorges, by the time Blake met up with Cuesta at Benavente, their combined forces totalled 22,000 men.
Moreover, imposing his seniority against the younger Blake's objections, Cuesta claimed supreme command and insisted on a foolhardy march on Valladolid to reclaim his lost city. Setting his columns marching on July 12, he laid his new, combined force vulnerable to a French counterattack. Paralyzed by disunity of command, the Spanish troops were defeated on 14 July at the Battle of Medina del Rio Seco, mainly due to Cuesta having failed to close the gap between his troops and Blake's.
On 11 October 1808, Blake personally entered Bilbao, forcing General Merlin to retreat 32 kilometres (20 mi) up the valley of Durango to Zornosa. Merlin had entered the city the previous August to suppress the revolt against King Joseph and in doing so, had, in the words of the king himself, ensured that the "fire of insurrection was quenched with the blood of twelve hundred men". These numbers were likely exaggerated as according to the source cited they fire bombed Bilbao port and took vessels from the city.