The Peninsular War (1808-1814) was a military conflict during the Napoleonic Wars in which the forces of France fought against an alliance of Spain, Portugal, and the United Kingdom. The war began when Napoleon invaded the Iberian Peninsula, aiming to enforce his control over the region. It involved significant battles, guerrilla warfare, and the eventual withdrawal of French troops. The conflict had a profound impact on the countries involved, leading to political changes and the rise of nationalism. The war ended with the defeat of French forces, contributing to the decline of Napoleon's power in Europe and paving the way for the restoration of the Spanish monarchy.