Whilst the United Kingdom was at war with Napoleonic France tensions between the United States and the British Empire were rising. In 1812 the United States declared war on the United Kingdom and tried to invade Canada. After three years of fighting both parties agreed on a peace and the status quo ante bellum was restored. The British-American War was the last military conflict between the British Empire and the United States. After the war a long-term alliance between Britain, Canada and America could develop.