The Battle of Pancorbo (or Zornoza) was one of the opening engagements in Napoleon's invasion of Spain.
On October 31, 1808, Marshal François Lefebvre bloodied the Army of Galicia under Lieutenant General Joaquín Blake but failed to encircle or destroy it, upsetting both the Emperor and the French strategic situation.
Under Napoleon's guidance, the French had made meticulous preparations to annihilate Blake's position and thereby crush the left wing of the Spanish front that stretched from Cantabria to the Mediterranean Sea. Owing to friction with the Spanish authorities and a lack of coordination by the Central Junta, Blake, for his part, had no confidence in the Spanish deployment and could do little but conduct a cautious advance in the direction of Bilbao.
Lefebvre's IV Corps included three infantry divisions and 36 cannon. Major-General Horace Sébastiani's 1st Division contained the 28th Light and 75th Line (3 battalions) and the 32nd and 58th Line (2 bns.). Maj-Gen Leval's 2nd Division was made up of the Dutch brigade and 2 bns. each of the 2nd Nassau, 4th Baden and Hesse-Darmstadt Gross-und-Erbprinz Regiments, and the Paris National Guard and Frankfurt battalions. Maj-Gen Eugene-Casimir Villatte's 3rd Division included 3 bns. each of the 27th Light, 63rd, 94th and 95th Line.
Blake's Army of Galicia contained three infantry divisions, a vanguard and a reserve. General Figueroa commanded the 1st Division (4,000), Gen Riquelme the 3rd Division (4,800), Gen Carbajal the 4th Division (3,500), Gen Mendizabal (2,900) the Vanguard and Gen Mahy the Reserve (3,000). Only six of Blake's guns came into action.
On October 31, Lefebvre disobeyed Napoleon's orders and launched his IV Corps into a premature attack against Blake at Pancorbo. Blake was deeply disturbed by the appearance of French forces and took immediate measures to withdraw his troops and guns. The Spanish infantry, fighting without artillery support, was swiftly thrown back but escaped in good order.
Lefebvre lost 200 casualties and Blake 600. Although the French had managed something of a tactical victory, the battle was a definite strategic blunder: Blake escaped the French trap and conducted a crafty withdrawal, checked his pursuers at Valmaseda, and was not caught until November 10. Ultimately, however, the overwhelming strength of Napoleon's Grande Armée allowed the French to sweep past the tottering Spanish defences and capture Madrid by year's end.