# History of Canada–United States relations

The history of the relationship between Canada and the United States deeply connects both nations.

## Post-Columbian era
### Colonial wars

Before the British conquest of French Canada in 1760, there had been a series of wars between the British and the French that were fought out in the colonies as well as in Europe and the high seas. In general, the British heavily relied on American colonial militia units, while the French heavily relied on their First Nation allies. The Iroquois Nation were important British allies. Much of the fighting involved ambushes and small-scale warfare in the villages along the border between New England and Quebec. The New England colonies had a much larger population than Quebec, so major invasions came from south to north. The First Nation allies, only loosely controlled by the French, repeatedly raided New England villages to kidnap women and children, and torture and kill the men. Those who survived were brought up as Francophone Catholics. The tension along the border was exacerbated by religion, the French Catholics and English Protestants had a deep mutual distrust. There was a naval dimension as well, involving privateers attacking enemy merchant ships.
England seized Quebec from 1629 to 1632, and Acadia in 1613 and again from 1654 to 1670; These territories were returned to France by the peace treaties. The major wars were (to use American names), King William's War (1689–1697); Queen Anne's War (1702–1713); King George's War (1744–1748), and from 1755 to 1763 the French and Indian War (known in Europe as the Seven Years’ War).
New England soldiers and sailors were critical to the successful British campaign to capture the French fortress of Louisbourg in 1745, and (after it had been returned by treaty) to capture it again in 1758.

## Post-American Revolution
### American Revolutionary War

At the outset of the American Revolutionary War, the American revolutionaries hoped the French Canadians in Quebec and the Colonists in Nova Scotia would join their rebellion. They were pre-approved for joining the United States in the Articles of Confederation. When northeastern Quebec was invaded, thousands joined the American cause and formed regiments that fought during the war; however, most remained neutral and some joined the British effort. Britain advised the French Canadians that the British Empire already enshrined their rights in the Quebec Act, which the American colonies had viewed as one of the Intolerable Acts. The American invasion was a fiasco and Britain tightened its grip on its northern possessions; in 1777, a major British invasion into New York led to the surrender of the entire British army at Saratoga and led France to enter the war as an ally of the U.S. The French Canadians largely ignored France's appeals for solidarity.
The American forces had much better success in southwestern Quebec, owing to the leadership of Virginia militia leader George Rogers Clark. In 1778, 200 men under Clark, supplied and supported mainly by Virginia, came down the Ohio River near Louisville, Kentucky, marched across southern Illinois, and then captured Kaskaskia without loss of life. From there, part of his men took Vincennes, but was soon lost to British Lieutenant Colonel Henry Hamilton, the commander at Fort Detroit. Clark later retook it in the Siege of Fort Vincennes in February 1779. Roughly half of Clark's militia in the theater were Canadian volunteers sympathetic to the American cause.
In the end, America won its independence and the Treaty of Paris compelled Britain to cede parts of southwestern Canada to them. Following America's independence, Canada became a refuge for about an estimated 70,000 or 15% of Loyalists who either wanted to leave the U.S. or were compelled by Patriot reprisals to do so. Among the original Loyalists, there were 3,500 free African Americans. Most went to Nova Scotia and in 1792, 1,200 migrated to Sierra Leone. About 2,000 black slaves were brought in by Loyalist owners; they remained slaves in Canada until the Empire abolished slavery in 1833. Around 85% of the loyalists remained in the new United States and became American citizens.

### War of 1812 (1812-1815)

The Treaty of Paris of 1783, which ended the American Revolutionary War, called for British forces to vacate all their forts south of the Great Lakes border. Britain refused to do so, citing the failure of the newly-independent United States to provide financial restitution for Loyalists who had lost property in the war. The Jay Treaty in 1795 with Great Britain resolved that lingering issue and the British departed the forts. Thomas Jefferson saw the nearby British presence as a threat to the United States, and so he opposed the Jay Treaty, and it became one of the major political issues in the United States at the time. Thousands of Americans immigrated to Upper Canada (Ontario) from 1785 to 1812 to obtain cheaper land and better tax rates prevalent in that province; despite expectations that they would be loyal to the U.S. if a war broke out, in the event they were largely non-political.
Tensions mounted again after 1805, erupting into the War of 1812 (1812-1815), when the United States Congress, approved / signed by the fourth President James Madison (1751-1836, served 1809-1817), declared war in June 1812 on Britain. The Americans were angered by British harassment of U.S. ships on the high seas and seizure of 6,000 sailors from American ships, severe restrictions against neutral American trade with France, and British support for hostile Native American tribes in Ohio and territories the U.S. had gained in 1783. American "honor" was an implicit issue. While the Americans could not hope to defeat the Royal Navy and control the seas, they could call on an army much larger than the British garrison in Canada, and so a land invasion of Canada was proposed as the most advantageous means of attacking the British Empire. Americans on the western frontier also hoped an invasion would bring an end to British support of Native American resistance to American expansion, typified by Tecumseh's coalition of tribes. Americans may also have wanted to acquire Canada.
Once war broke out, the American strategy was to seize Canada. There was some hope that settlers in western Canada—most of them recent immigrants from the U.S.—would welcome the chance to overthrow their British rulers. However, the American invasions were defeated primarily by British regulars with support from Native Americans and Upper Canada militia. Aided by the large Royal Navy, a series of British raids on the American coast were highly successful, culminating with an attack on Washington that resulted in the British burning of the White House, the Capitol, and other public buildings. At the end of the war, Britain's American Indian allies had largely been defeated, and the Americans controlled a strip of Western Ontario centered on Fort Malden. However, Britain held much of Maine, and, with the support of their remaining American Indian allies, huge areas of the Old Northwest, including Wisconsin and much of Michigan and Illinois. With the surrender of Napoleon in 1814, Britain ended naval policies that angered Americans; with the defeat of the Indian tribes, the threat to American expansion was ended. The upshot was both the United States and Canada asserted their sovereignty, Canada remained under British rule, and London and Washington had nothing more to fight over. The war was ended by the Treaty of Ghent, which took effect in February 1815. A series of postwar agreements further stabilized peaceful relations along the Canada–US border. Canada reduced American immigration for fear of undue American influence and built up the Anglican Church of Canada as a counterweight to the largely American Baptist and Methodist churches.
In later years, Anglophone Canadians, especially in Ontario, viewed the War of 1812 as a heroic and successful resistance against invasion and as a victory that defined them as a people. The myth that the Canadian militia had defeated the invasion almost single-handed, known logically as the "militia myth", became highly prevalent after the war, having been propounded by John Strachan, Anglican Bishop of York.

### Post-War of 1812 and mid-19th century

In the aftermath of the War of 1812, pro-British conservatives led by Anglican Bishop John Strachan took control in Ontario ("Upper Canada") and promoted the Anglican religion as opposed to the more republican Methodist and Baptist churches. A small interlocking elite, known as the Family Compact took full political control. Democracy, as practiced in the United States, was ridiculed. The policies had the desired effect of deterring immigration from the United States. Revolts in favor of democracy in Ontario and Quebec ("Lower Canada") in 1837 were suppressed; many of the leaders fled to the US. The American policy was to largely ignore the rebellions, and indeed ignore Canada generally in favor of the westward expansion of the American Frontier.
The Webster–Ashburton Treaty formalized the U.S.–Canada border in Maine, averting the Aroostook War. During the Manifest Destiny era, the "Fifty-Four Forty or Fight" agenda called for U.S. annexation of what became Western Canada; the U.S. and Britain instead agreed to a boundary of the 49th parallel. As harsher fugitive slave laws were passed, Canada became a destination for slaves escaping on the Underground Railroad.

## Post-American Civil War
### American Civil War

The British Empire was neutral during the American Civil War. About 40,000 Canadians volunteered for the Union Army—many already lived in the U.S., and a few for the Confederate Army. However, hundreds of Americans who were called up in the draft fled to Canada.
Several events caused strained relations between the British Empire and the United States, over the former's unofficial role in supporting the Confederacy. Blockade runners loaded with arms came from Great Britain and made use of Canadian ports in the Maritimes to break through the Union blockade to deliver the weaponry to the Confederacy in exchange for cotton. Attacks were made on American merchant shipping by British-built Confederate warships such as CSS Alabama. On December 7, 1863, pro-Confederate Canadian sympathizers hijacked an American steamer and killed a crew member off the coast of Cape Cod, Massachusetts then used the steamer, originally intended as a blockade runner, to flee back to the Maritimes where they were later able to escape justice for murder and piracy. Confederate Secret Service agents also used Canada as a base to attack American border towns, such as St. Albans, Vermont on October 19, 1864, where they killed an American citizen, robbed three banks of over US$200,000, then escaped to Canada where they were arrested but then released by a Canadian court to widespread American anger. Many Americans falsely suspected that the Canadian government knew of the raid ahead of time. American Secretary of State William H. Seward let the British government know that "it is impossible to consider those proceedings as either legal, just or friendly towards the United States."

#### Alabama claims

Americans were angry at Britain's perceived support for the Confederacy during the American Civil War. Some leaders demanded a huge payment, on the premise that British involvement had lengthened the war by two years, a claim confirmed by post-Civil War historians and scholars. Senator Charles Sumner, the chairman of the Senate Foreign Relations Committee, originally wanted to ask for $2 billion in war reparations, or alternatively the ceding of all of Canada to the United States.
When American Secretary of State William H. Seward negotiated the Alaska Purchase with Russia in 1867, he intended it as the first step in a comprehensive plan to gain control of the entire northwest Pacific Coast. Seward was a firm believer in Manifest Destiny, primarily for its commercial advantages to the U.S. Seward expected British Columbia to seek annexation to the U.S. and thought Britain might accept this in exchange for the Alabama claims. Soon other elements endorsed annexation, they planned to annex British Columbia, Red River Colony (Manitoba), and Nova Scotia, in exchange for dropping the damage claims. The idea peaked in the spring and summer of 1870, with American expansionists, Canadian separatists, and pro-American Englishmen seemingly combining forces. The plan was dropped for multiple reasons. London continued to stall, American commercial and financial groups pressed Washington for a quick settlement of the dispute on a cash basis, growing Canadian nationalist sentiment in British Columbia called for staying inside the British Empire, Congress became preoccupied with Reconstruction, and most Americans showed little interest in territorial expansion.
The "Alabama Claims" dispute went to international arbitration. In one of the first major cases of arbitration, the tribunal in 1872 rejected the American claims for damages relating to the British blockade running but ordered Britain to pay $15.5 million only for damages caused by British-built Confederate ships. Britain paid and the episode ended in peaceful relations.

### Late 19th century

Canada became a self-governing dominion in 1867 in internal affairs while Britain retained control of diplomacy and defence policy. Before Confederation, there was an Oregon boundary dispute in which the Americans claimed the 54th degree latitude. The Oregon Treaty of 1846 largely resolved the issue, splitting the disputed territory – the northern half became British Columbia, and the southern half eventually formed the states of Washington and Oregon.
Strained relations with America continued, however, due to a series of small-scale armed incursions called the "Fenian raids" conducted by Irish-American Civil War veterans across the border from 1866 to 1871 in an attempt to trade Canada for Irish independence. The American government, angry at Canadian tolerance of Confederate raiders during the American Civil War of 1861 to 1865, moved very slowly to disarm the Fenians. The Fenian raids were small-scale attacks carried out by the Fenian Brotherhood, an Irish Republican organization based among Irish Catholics in the United States. Targets included British Army forts, customs posts, and other locations near the border. The raids were small, unsuccessful episodes in 1866, and again from 1870 to 1871. They aimed to bring pressure on Great Britain to withdraw from Ireland. None of these raids achieved their aims and all were quickly defeated by local Canadian forces.
The British government, in charge of diplomatic relations, protested cautiously, as Anglo-American relations were tense. Much of the tension was relieved as the Fenians faded away and in 1872 by the settlement of the Alabama Claims, when Britain paid the U.S. $15.5 million for war losses caused by warships built in Britain and sold to the Confederacy.
Disputes over ocean boundaries on Georges Bank and fishing, whaling, and sealing rights in the Pacific were settled by international arbitration, setting an important precedent.

### Early 20th century
#### Alaska boundary

A short-lived controversy was the Alaska boundary dispute, settled in favor of the United States in 1903. The issue was unimportant until the Klondike Gold Rush brought tens of thousands of men to Canada's Yukon, and they had to arrive through American ports. Canada needed its port and claimed that it had a legal right to a port near the present American town of Haines, Alaska. It would provide an all-Canadian route to the rich goldfields. The dispute was settled by arbitration, and the British delegate voted with the Americans—to the astonishment and disgust of Canadians who suddenly realized that Britain considered its relations with the United States paramount compared to those with Canada. The arbitration validated the status quo, but made Canada angry at London.
1907 saw a minor controversy over USS Nashville sailing into the Great Lakes via Canada without Canadian permission. To head off future embarrassments, in 1909 the two sides signed the International Boundary Waters Treaty, and the International Joint Commission was established to manage the Great Lakes and keep them disarmed. It was amended in World War II to allow the building and training of warships.

#### Free trade rejected

Anti-Americanism reached a shrill peak in 1911 in Canada. The Liberal government in 1911 negotiated a Reciprocity treaty with the U.S. that would lower trade barriers. Canadian manufacturing interests were alarmed that free trade would allow the bigger and more efficient American factories to take their markets. The Conservatives made it a central campaign issue in the 1911 election, warning that it would be a "sell-out" to the United States with economic annexation a special danger. The Conservative slogan was "No truck or trade with the Yankees", as they appealed to Canadian nationalism and nostalgia for the British Empire to win a major victory.

#### World War I

British Canadians were annoyed during a brief period from 1914 to 1916, when the United States insisted on neutrality and seemed to profit heavily, while Canada was sacrificing its wealth and its youth. However, when the U.S. finally declared war on Germany in April 1917, there was swift cooperation and friendly coordination, as one historian reports:
   Official co-operation between Canada and the United States—the pooling of grain, fuel, power, and transportation resources, the underwriting of a Canadian loan by bankers of New York—produced a good effect on the public mind. Canadian recruiting detachments were welcomed in the United States, while a reciprocal agreement was ratified to facilitate the return of draft evaders. A Canadian War Mission was established at Washington, and in many other ways, the activities of the two countries were coordinated for efficiency. Immigration regulations were relaxed and thousands of American farmhands crossed the border to assist in harvesting Canadian crops. Officially and publicly, at least, the two nations were on better terms than ever before in their history, and on the American side, this attitude extended through almost all classes of society.

#### Post-World War I

Canada demanded and received permission from London to send its delegation to the Versailles Peace Talks in 1919, with the proviso that it sign the treaty under the British Empire. Throughout the 1920s, Canada began assuming greater responsibility for its own foreign and military affairs. In 1927, the U.S. and Canada exchanged ambassadors for the first time with Canada appointing Vincent Massey and America William Phillips respectively. The postwar era saw the United States pursue isolationism while Canada became an active member of the British Commonwealth, the League of Nations, and the World Court.
In July 1923, as part of his Pacific Northwest tour and a week before his death, U.S. President Warren Harding visited Vancouver, making him the first American head of state to visit confederated Canada. The then Premier of British Columbia, John Oliver, and then mayor of Vancouver, Charles Tisdall, hosted a lunch in his honor at the Hotel Vancouver. Over 50,000 people heard Harding speak in Stanley Park. A monument to Harding designed by Charles Marega was unveiled in Stanley Park in 1925.
Relations with the United States remained cordial until 1930 when Canada vehemently protested the new Smoot–Hawley Tariff Act by which the U.S. raised tariffs on products imported from Canada. Canada retaliated with higher tariffs of its own against American products and moved toward more trade within the British Commonwealth. U.S.–Canadian trade fell 75% as the Great Depression dragged both countries down.
During the 1920s, the war and naval departments of both nations designed war game scenarios with the other as an enemy as part of routine training exercises. In 1921, Canada developed Defence Scheme No. 1 for an attack on American cities and for forestalling an invasion by the United States until British reinforcements could arrive. Throughout the later 1920s and 1930s, the United States Army War College developed a plan for a war with the British Empire waged largely on North American territory: War Plan Red.
Herbert Hoover's meeting in 1927 with British Ambassador Sir Esme Howard agreed on the "absurdity of contemplating the possibility of war between the United States and the British Empire".
In 1938, as the roots of World War II were set in motion, U.S. President Franklin Roosevelt gave a public speech at Queen's University in Kingston, Ontario, declaring that the United States would not sit idly by if another power tried to dominate Canada. Diplomats saw it as a clear warning to Germany not to attack Canada.

### World War II

The two nations cooperated closely in World War II, as both nations saw new levels of prosperity and a determination to defeat the Axis powers. Prime Minister William Lyon Mackenzie King and President Franklin D. Roosevelt were determined not to repeat the mistakes of their predecessors. They met in August 1940 at Ogdensburg, issuing a declaration calling for close cooperation, and formed the Permanent Joint Board on Defense (PJBD).
King sought to raise Canada's international visibility by hosting the August 1943 Quadrant conference in Quebec on military and political strategy; he was a gracious host but was kept out of the important meetings by Winston Churchill and Roosevelt.
Canada allowed the construction of the Alaska Highway and participated in the building of the atomic bomb. 49,000 Americans joined the RCAF (Canadian) or RAF (British) air forces through the Clayton Knight Committee, which had Roosevelt's permission to recruit in the U.S. in 1940–42.
American attempts in the mid-1930s to integrate British Columbia into a united West Coast military command had aroused Canadian opposition. Fearing a Japanese invasion of Canada's vulnerable British Columbia Coast, American officials urged the creation of a united military command for an eastern Pacific Ocean theater of war. Canadian leaders feared American imperialism and the loss of autonomy more than a Japanese invasion. In 1941, Canadians successfully argued within the PJBD for cooperation rather than the unified command for the West Coast.

#### Newfoundland

The United States built large military bases in Newfoundland during World War II. At the time it was a British crown colony, having lost dominion status. The American spending ended the depression and brought new prosperity; Newfoundland's business community sought closer ties with the United States as expressed by the Economic Union Party. Ottawa took notice and wanted Newfoundland to join Canada, which it did after hotly contested referendums. There was little demand in the United States for the acquisition of Newfoundland, so the United States did not protest the British decision not to allow an American option on the Newfoundland referendum.

## Contemporary era
### Cold War

Prime Minister William Lyon Mackenzie King, working closely with his Foreign Minister Louis St. Laurent, handled foreign relations 1945–48 cautiously. Canada donated money to the United Kingdom to help it rebuild; was elected to the UN Security Council; and helped design NATO. However, Mackenzie King rejected free trade with the United States, and decided not to play a role in the Berlin airlift. Canada had been actively involved in the League of Nations, primarily because it could act separately from Britain. It played a modest role in the postwar formation of the United Nations, as well as the International Monetary Fund. It played a somewhat larger role in 1947 in designing the General Agreement on Tariffs and Trade. After the mid-20th century onwards, Canada and the United States became extremely close partners. Canada was a close ally of the United States during the Cold War.

#### Vietnam War resisters

While Canada openly accepted draft evaders and later deserters from the United States, there was never a serious international dispute due to Canada's actions, while Sweden's acceptance was heavily criticized by the United States. The issue of accepting American exiles became a local political debate in Canada that focused on Canada's sovereignty in its immigration law. The United States did not become involved because American politicians viewed Canada as a geographically close ally not worth disturbing.

#### Nixon Shock 1971

The United States had become Canada's largest market, and after the war, the Canadian economy became dependent on smooth trade flows with the United States so much that in 1971 when the United States enacted the "Nixon Shock" economic policies (including a 10% tariff on all imports) it put the Canadian government into a panic. Washington refused to exempt Canada from its 1971 New Economic Policy, so Canadian prime minister Pierre Trudeau saw a solution in closer economic ties with Europe. Trudeau proposed a "Third Option" policy of diversifying Canada's trade and downgrading the importance of the American market. In a 1972 speech in Ottawa, Nixon declared the "special relationship" between Canada and the United States dead.
Relations deteriorated on many points in the Nixon years (1969–74), including trade disputes, defense agreements, energy, fishing, the environment, cultural imperialism, and foreign policy. They changed for the better when Trudeau and Carter found a better rapport. The late 1970s saw a more sympathetic American attitude toward Canadian political and economic needs, the pardoning of draft evaders who had moved to Canada, and the passing of old such as the Watergate scandal and the Vietnam War. Canada more than ever welcomed American investments during "the stagflation" that hurt both nations.

### 1990s

The main issues in Canada–US relations in the 1990s focused on the North American Free Trade Agreement, which was signed in 1994. It created a common market that by 2014 was worth $19 trillion, encompassed 470 million people, and had created millions of jobs. Wilson says, "Few dispute that NAFTA has produced large and measurable gains for Canadian consumers, workers, and businesses". However, he adds, "NAFTA has fallen well short of expectations."

### Early 21st century

During his 2024 campaign and continuing into his second presidency, Donald Trump spoke repeatedly about imposing tariffs on Canada and making Canada the 51st U.S. state. On November 29, 2024, Trudeau met with Trump to address trade issues after Trump threatened a 25% tariff on Canadian imports and planned to rethink the USMCA. Trudeau warned of retaliation if tariffs were enacted. Trump continued his comments throughout December, calling Canada a state and Trudeau a governor. On December 18, he claimed many Canadians supported the idea of becoming the 51st state. Trudeau firmly rejected any possibility of annexation on January 7. In early February 2025, Trudeau announced retaliatory tariffs of 25% against the United States on CA$155 billion worth of U.S. goods.

## Migration history

From the 1750s to the 21st century, there has been an extensive mingling of the Canadian and American populations, with large movements in both directions.
New England Yankee settled large parts of Nova Scotia before 1775 and were neutral during the American Revolution. At the end of the American Revolution, about 75,000 United Empire Loyalists moved out of the new United States to the eastern Atlantic provinces and south of Quebec. From 1790 to 1812 many farmers moved from New York and New England into Upper Canada (mostly to Niagara, and the north shore of Lake Ontario). In the mid and late 19th century gold rushes attracted American prospectors, mostly to British Columbia after the Cariboo Gold Rush, Fraser Canyon Gold Rush, and later to the Yukon Territory. In the early 20th century, the opening of land blocks in the Prairie Provinces attracted many farmers from the American Midwest. Many Mennonites immigrated from Pennsylvania and formed their colonies. In the 1890s some Mormons went north to form communities in Alberta after the Church of Jesus Christ of Latter-day Saints rejected plural marriage. The 1960s saw the arrival of about 50,000 draft-dodgers who opposed the Vietnam War.
Canada was a way station through which immigrants from other lands stopped for a while, ultimately heading to the U.S. Between 1851 and 1951, 7.1 million people arrived in Canada (mostly from Continental Europe), and 6.6 million left Canada, most of them to the U.S. After 1850, the pace of industrialization and urbanization was much faster in the United States, drawing a wide range of immigrants from the North. By 1870, 1/6 of all the people born in Canada had moved to the United States, with the highest concentrations in New England, which was the destination of Francophone emigrants from Quebec and Anglophone emigrants from the Maritimes. It was common for people to move back and forth across the border, such as seasonal lumberjacks, entrepreneurs looking for larger markets, and families looking for jobs in the textile mills that paid much higher wages than in Canada.
The southward migration slacked off after 1890, as Canadian industry began a growth spurt. By then, the American frontier was closing, and thousands of farmers looking for fresh land moved from the United States north into the Prairie Provinces. The net result of the flows was that in 1901 there were 128,000 American-born residents in Canada (3.5% of the Canadian population) and 1.18 million Canadian-born residents in the United States (1.6% of the U.S. population).
In the late 19th and early 20th centuries, about 900,000 French Canadians moved to the U.S., with 395,000 residents there in 1900. Two-thirds went to mill towns in New England, where they formed distinctive ethnic communities. By the late 20th century, most had abandoned the French language (see New England French), but most kept the Catholic religion. About twice as many English Canadians came to the U.S., but they did not form distinctive ethnic settlements.