The Peninsular theatre of the Napoleonic Wars began in 1807 when France and Spain invaded Portugal and was then further escalated when France took over the Spanish throne in 1808. The Spanish rejected French rule and fought back to remove them. Britain responded by sending troops to reinforce Portugal, succeeding in securing the country and reforming their army to take on the French. Led by Wellington, the combined Anglo-Portuguese army fought alongside the Spanish for several years. Napoleon's il-fated campaign into Russia in 1812 led to severely depleted French forces and they were eventually defeated and forced to retreat back over the Pyrenees in the winter of 1813-14.