U.S. And Canada Once Nearly Went To War Over A Pig and Other Tense Moments in Canadian-American History

The U.S. and Canada have long enjoyed a peaceful relationship as next-door neighbors and key allies, but growing tensions between the two countries over President Donald Trump's decision to introduce significant steel, aluminum and auto tariffs on Canada have raised concerns over the future of relations between the North American countries.

After a war of words, with Trump calling Canada's Prime Minister Justin Trudeau "meek and mild" after the Canadian leader said the tariffs were "insulting," the U.S. released an updated Northern Border Strategy, promising a "strengthened" approach to secure the U.S.'s border with Canada.

While tensions between the two countries have rarely been so fraught, this is not the first time the U.S. government or American citizens have seen clashes with their northern neighbors. Here are six moments in history that saw conflict at the U.S.-Canada border:

1. The American Revolution (1775)

At the start of the American Revolution in 1775, the Continental Army launched an invasion on the British colony of Canada. In a bid to seize Quebec City, patriots sought to recruit French Canadians to join their rebellion. The rebel forces were ultimately defeated in Canada, but 13 colonies were able to declare independence by 1776 or confirm it by war and treaty in 1783.

2. The War of 1812 (1812-1814)

The War of 1812 made it into headlines recently after Trump asked Trudeau during a phone call whether Canada had burned down the White House during the prominent war. Asked by Trudeau how he could justify calling his tariffs a "national security" issue, Trump said: "Didn't you guys burn down the White House?"

In fact, the White House was burned down by British troops during the war, which unfolded more than 50 years before Canada had even been founded as a country.

The conflict, which began after the United States declared war on Great Britain in June 1812, ultimately ended in a deadlock, with both sides returning all territorial conquests with the signing of the treaty of Ghent on December 24, 1814.

Despite former President Thomas Jefferson's assurances that "the acquisition of Canada" would be a "mere matter of marching," Americans were not welcomed as liberators and saw little support from locals, according to an archived page from History.com.

3. Patriot War (1838)

The Patriot War saw conflict along the U.S.-Canada border during which Americans launched a series of attacks against the British colony of Upper Canada. Americans rose up in support of the Canadian rebellion in Upper Canada, which was initiated by Canadian journalist William Lyon Mackenzie.

Canadians and Americans formed secret groups known as "Hunters Lodges" where they plotted how to free Canada from British rule.

As many as 50 rebels were killed in the Battle of the Windmill that ensued, with nearly a dozen more being executed for treason, according to History.com.

The rebels only disbanded a few weeks later, however, after a failed invasion by rebels crossing the Detroit River into Windsor forced the group to disband.

4. Pork and Beans War (1838-1839)

It was in the late 1830s that the U.S. saw the only instance in which a state went to war with a foreign country, historian and author of "War Plan Red," Kevin Lippert writes in his book on relations between the U.S. and Canada.

An ongoing dispute between Maine and the Canadian province of New Brunswick over lumberjacks' rights to cut down trees on the U.S.-Canada border sparked what came to be known as the "Pork and Beans War."

The war, which was named after local lumberjacks' favorite meal, according to Lippert, started after U.S. officials sent a volunteer militia to confiscate equipment from any New Brunswick lumberjack found cutting trees on American soil.

The militia was captured by the Canadians, however, Lippert says, and taken to a barracks in Woodstock, New Brunswick.

The U.S. Congress "authorized a force of 50, 000 men and $10 million under the command of General Winfield 'Old Fuss and Feathers' Scott," according to Lippert, but ultimately, tensions died down quickly, without a single shot being fired, the historian said.

The U.S. and Canada redrew their border "in a way that gave more land to the States than to Canada" Lippert wrote, because "the whole territory...was worth nothing."

5. The Pig War (1859)

A dead hog was at the center of another dispute that nearly led to war between the U.S. and Canada in June 1859.

The conflict started when American farmer Lyman Cutlar killed a large black pig that had been owned by the Canadian Hudson's Bay Company after he caught it eating potatoes in his garden in the San Juan Islands, an archipelago in Washington, according to History.com.

When British authorities threatened to arrest Cutlar and evict others from the islands, the U.S. Army dispatched as many as 64 soldiers under Captain George Pickett to the island to resolve the dispute.

Ultimately, British and American troops were able to peacefully occupy the islands until an arbitration commission ruled that the they were American territories.

6. The Fenian Raids (1866-1871)

The Fenian raids saw the Fenian Brotherhood, an Irish Republican organization based in the U.S., attack British army forts and other targets in Canada in an effort to pressure the British into withdrawing from Ireland, according to the Canadian War Museum's website.

By capturing Canada as a hostage, the brotherhood, composed largely of Irish-American veterans, hoped to help secure Ireland's independence from Britain.

They raided Canadian territory from New Brunswick to Manitoba between the years of 1866 and 1871, defeating a small Canadian force in Ridgeway, Ontario during the largest raid, which took place in June 1866 along the Niagara frontier, the website states.

However, the brotherhood's members returned to the U.S. before Canadian and British reinforcements could arrive and the movement itself fell apart after 1871.