(June 21, 1813), decisive battle of the Peninsular War that finally broke Napoleon's power in Spain. The battle was fought between a combined English, Spanish, and Portuguese army numbering 72,000 troops and 90 guns under Arthur Wellesley, 1st duke of Wellington (Wellington, Arthur Wellesley, 1st duke of, marquess of Douro, marquess of Wellington, earl of Wellington, Viscount Wellington of Talavera and of Wellington, Baron Douro or Wellesley), and a French army numbering 57,000 troops and 150 guns commanded by King Joseph Bonaparte (Bonaparte, Joseph). The French occupied a defensive position in the basin of Vitoria (Vitoria-Gasteiz), an area about 12 mi (19 km) long and 7 mi deep, surrounded by mountains and protected to the north and west by the Zadorra River, which was spanned by several lightly held bridges. Just after 8 AM the allies advanced in four columns against the whole front, crossed the river at several bridges to the west, and eventually compelled the French left and centre to withdraw in order to cover Vitoria. The French right, after heavy fighting, finally gave way. By 7 PM the French were in full retreat toward Pamplona, leaving behind vast quantities of plunder, baggage, and all their artillery. The French losses (killed, wounded, and captured) were about 8,000 and those of the allies about 5,000. By their victory the British and their allies gained control of the Basque provinces, and compelled the French forces to retreat over the Pyrenees and back into France.