Roncesvalles Pass - 25 July 1813

Historical Background
This high mountain pass, in the Pyrenees on the border between France and Spain, is famous since Roland de Roncevaux (nephew of Charlemagne) died in 15 August 778, commanding the rearguard of Charlemagne’s army.
After the defeat of King Joseph at Vitoria, Wellington concentrated his efforts on capturing the port of San Sebastián and the town of Pamplona, the last French outposts on the Spanish soil. He also sent 11,000 men to cover the main passes over the Pyrenees mountains. Having rapidly rebuilt and reorganised his forces after their defeat, the French under Marshal Soult launched an attack towards Pamplona through the passes of Maya and Roncesvalles. The main French attack was at Roncesvalles where the pass was defended by the British 4th Division (Cole), Byng's brigade of the 2nd Division and the Portuguese 4/10 brigade. The French attacked from Saint-Jean-Piedde-Port, advancing in two columns either side of the pass, Clausel on the Altobiscar and Reille on the Linduz. The British were badly outnumbered, but fought steadily. Byng's brigade on the eastern side held Clausel's division at bay for three hours before being forced back. In the afternoon Cole brought up three more brigades as reinforcements. However around 5:00 pm, a dense fog descended over the battlefield, just as the Portuguese 4/10 brigade repelled French attacks in the Val de Baigorry. Cole, despite orders to the contrary, ordered his troops to retreat towards Pamplona. Following the defeat at Roncesvalles, the Allied forces were obliged to retreat southwards towards Pamplona and regrouped near the village of Sorauren.
Wellington admitted later that splitting his forces in order to besiege both San Sebastián and Pamplona simultaneously was "one of the greatest faults he ever committed in war".
( Source : Wikipedia )
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