Americans also fought the British and allied Indigenous peoples in the Ohio Country — what was then the southwest of Quebec; at the end of the war, the land south of the Great Lakes was ceded to the newly independent United States and became the Northwest Territory.

[1][2] Confederate agents operating in Canada received support from a large portion of Canadians throughout the war, allowing the British colony to be used as a base to attack the U.S., such as in the St. Albans Raid.

Groups of Irish immigrants took the route of armed struggle, attempting to annex the peninsula between the Detroit and Niagara Rivers to the U.S. by force in the minor and short-lived Patriot War in 1837–1838.

Notably, Canada's population growth in the late 18th and early 19th centuries was spurred largely by United Empire Loyalists, who left the American colonies during the Revolution because of their loyalty to Great Britain.

[8] Around 1850 there was a serious annexationist movement on the border region of Quebec's Eastern Townships, where the American-descended majority felt that union with the United States would end their economic isolation and stagnation as well as remove them from the growing threat of French Canadian political domination.

[9] In Montreal at midcentury, with little immigration and complaints that the repeal of the Corn Laws had cut the region off from its British trade links, a small but organized group supported integrating the colonies into the United States.

Nova Scotia anti-confederationists led by Joseph Howe felt that pro-confederation premier Charles Tupper had caused the province to agree to join Canada without popular support.

A significant economic downturn occurred after the end after 1866 of the Reciprocity Treaty of 1854; the colony was heavily dependent on selling fish to Americans, causing many to believe that free trade with the United States was necessary for prosperity.

The provincial government, dominated by extremists who now also opposed Howe, decided that if another appeal to London failed it would seize federal offices and unilaterally declare annexation, believing that Britain would not use force to stop Nova Scotia.

(The author attributed the absence of an active annexationist movement in part to many who would favor such an effort taking the "easiest and quietest method of securing the benefits of annexation, by themselves silently migrating to the Republic", as more than a million already had.

Bender concluded with pessimism about the likelihood of success of a nation divided in two parts by 1,200 miles of "forbidding, silent wilderness stretching from the head-waters of the Ottawa to Thunder Bay, and thence to Manitoba".

[16] In January 1893, concerned about Canada's possible annexation, a goal then being pursued by the Continental Union Association, a group of Ontario and Quebec Liberals, Prime Minister Sir John Thompson delivered a speech on tolerance, Canadian nationalism and continued loyalty to Britain.

Stead cited several reasons for why he believed annexation seemed "inevitable", however, including rapidly growing economic ties and migration between the two countries, the French Shore, and disputes over the Alaska boundary and fishing rights in the Atlantic.

[27][28][29] During an appearance on Fox News, Ontario Premier Doug Ford humorously referred to the situation as former U.S. President Donald Trump’s attempt at revenge for the War of 1812 (which took place before Canada's independence), and that he might still harbor a 212-year-old grudge over the burning of the White House by British forces.

[36] Following speculation regarding Trudeau's resignation, Trump reiterated his annexation proposals, claiming that this move would enhance trade and bolster national security by eliminating the border.

In a post on his Truth Social platform, Trump cited several factors, including the perceived Canadian interest for the idea, alleged U.S. deficits and subsidies, and the notion that these circumstances contributed to Trudeau's resignation.

Speaking at the World Economic Forum on January 23, Trump dismissed Canada’s importance as a trade partner, asserting that the United States does not rely on Canadian oil, gas, vehicles, or lumber.

"[67][68] President Trump's proposals have been received broadly negatively in Canada, with it being condemned by all major political parties and leaders as well as causing increasing strain on Canadian - U.S. relations.

[72][73] Canada's head of state, King Charles III, and his representative, the Governor General, have not commented on Trump's proposals, due to the non-partisan role they play in the Canadian political system.

Key issues driving separatist sentiment include a perceived power imbalance with Ottawa, long-standing economic grievances,[2] a distinct cultural identity, and dissatisfaction with federal policies—particularly those affecting Alberta's energy sector.

Although financial restrictions were lifted after two weeks, the incident amplified existing grievances, including government overreach on gun control, high taxes, and centralized management of Alberta's natural resources.

Premier Jason Kenney reiterated the belief that Alberta’s economic contributions are often overlooked or undervalued, echoing a historic desire for greater recognition and autonomy from the federal government.

[110] On 12 January, Premier Danielle Smith set up an impromptu meeting with U.S. President-elect Donald Trump at his Mar-a-Lago residence in Florida, as a guest of Canadian businessman and television personality Kevin O’Leary,[111] discussing U.S.-Canadian energy relations.

[120] In response to U.S. President Donald Trump’s claim at the World Economic Forum on January 23 that the United States does not rely on Canadian oil, gas, vehicles, or lumber, Smith maintained a diplomatic stance.

She then urged the federal government to address concerns raised by Trump regarding border security and defense spending, while affirming that his remarks at the World Economic Forum have not altered her stance.

Any shift in sovereignty would require complex negotiations, such as adopting new tax structures, renegotiating trade agreements, and determining how to manage Alberta's extensive national parks and public lands.

[102] Jordan Peterson, an Alberta-born United States resident media commentator,[133] describes Alberta’s position as increasingly tenuous, caught between federal policies that he claims stifle the province’s energy industry and a U.S. administration that perceives Canada as economically dependent.

He outlines potential economic advantages Alberta could gain by joining the United States, including lower taxes, improved market access, and enhanced infrastructure support.

[141][142] On 8 December 2024, responding to Trump's Annexation proposal, Green Party leader Elizabeth May humorously suggested California, Oregon, and Washington join Canada instead, reviewing the idea of the Cascadia Movement.

[144] Canadian author Don Tapscott analyzed and proposed conditions for a merger, including preserving Canada's healthcare system, maintaining provincial identities as states, and introducing legal reforms on campaign finance, education funding, and gun control.