The Peninsular War(i) pitted an alliance of Spain, Portugal, and United Kingdom against France on the Iberian Peninsula during the Napoleonic Wars. The war began when French armies occupied Spain in 1808 and lasted until the Sixth Coalition defeated Napoleon in 1814.Spain's liberation struggle marked one of the first national wars and was among the first modern, large-scale guerrilla conflicts, from which the English language borrowed the word. Its success was in part decided by the exploits of Spanish guerrillas and the inability of Napoleon Bonaparte's large armies to pacify the people of Spain: French units in Spain, forced to guard their vulnerable supply lines, were always in danger of being cut off and overwhelmed by the partisans, and proved unable to stamp out the Spanish army.
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