The United States and Great Britain after the War of 1812 frequently came into conflict during the Nineteenth Century, and it is a medium sized miracle that one of these conflicts did not end in a third Anglo-American War. The most surreal of these conflicts, beyond a doubt, is the Pig War of 1859.
Both Great Britain and America claimed the San Juan Islands lying between Vancouver Island and the then Washington territory, and the islands were settled by British subjects and American citizens. On June 15, 1859 Lyman Cutlar, an American farmer on San Juan island, came out and found a pig eating tubers in his garden. This was not the first incident involving the wayward pig, and Cutlar shot the pig, killing the porcine invader. The pig was owned by a British subject, Charles Griffin, who took umbrage at the slaying of his wandering porker. The two men had words about the pig. British authorities threatened to arrest Cutlar, and the American settlers called for American military protection.
By August 10, 1859, 461 American soldiers with 14 cannon confronted five British warships carrying 2,140 men. Fortunately, both sides exercised restraint and no shots were fired. James Douglas, the governor of British Vancouver, ordered British Rear Admiral Robert L. Baynes to land Royal Marines on San Juan island and engage the Americans. Baynes flatly refused, saying that for two great nations to come to blows over a squabble over a pig was foolish. London and Washington were equally aghast at the idea of going to war over this case of porcinecide, and General Winfield Scott was sent by President Buchanan to Vancouver to negotiate with Governor Douglas. Agreement was reached that the British and American forces would be reduced to a 100 men each on San Juan island while negotiations were underway between the countries. Ultimately third party arbitration, by Kaiser Wilhelm I of Germany, led to the islands being awarded to America in 1872.