Anger at British naval actions led the United States to declare war on Britain in the War of 1812, but it did not become an ally of France. Grievances over control of Poland, and Russia's withdrawal from the Continental System, led to Napoleon invading Russia in June 1812. The invasion was an unmitigated disaster for Napoleon; scorched earth tactics, desertion, French strategic failures and the onset of the Russian winter compelled Napoleon to retreat with massive losses. Napoleon suffered further setbacks; French power in the Iberian Peninsula was broken at Battle of Vitoria the following summer, and a new coalition began the War of the Sixth Coalition.