By 1812 the young United States was frustrated with Britain. This section explains why war broke out and what it changed for both British North America and the United States.
- Impressment — Britain seizing US sailors and forcing them into the Royal Navy, which the US saw as an insult to its sovereignty.
- Orders in Council — British trade restrictions that blocked US ships from trading with France during the Napoleonic Wars, hurting US merchants.
- British support for Native resistance — Britain armed and encouraged Indigenous confederacies (led by Tecumseh) on the US frontier, blocking American westward expansion.
- War Hawks — young Congressmen like Henry Clay who wanted war, partly hoping to seize Canada while Britain was busy fighting Napoleon.
Why the US declared war in 1812: President James Madison asked Congress for war in June 1812. It was a mix of maritime grievances (impressment, trade rules) and expansionist ambition — many in Congress believed capturing Canada would be, in Henry Clay's words, "a mere matter of marching."
That prediction was wrong. US invasions of Canada in 1812–1813 failed repeatedly. British troops, Canadian militia, and Indigenous allies under Tecumseh defended Upper Canada successfully, including at Queenston Heights (1812). Tecumseh was killed at the Battle of the Thames in 1813, a major blow to Native resistance in the region.
| Event | Year | Outcome |
|---|---|---|
| US invasions of Upper Canada | 1812–1813 | Repelled; failed to capture Canada |
| Battle of the Thames (Tecumseh killed) | 1813 | Native confederacy weakened badly |
| British burn Washington DC | 1814 | White House burned in retaliation |
| Treaty of Ghent | 1814 | War ends; borders return to pre-war (status quo ante bellum) |
Impact on British North America and the US: For British North America: successfully resisting invasion built an early sense of Canadian identity and loyalty to Britain, and confirmed the border with the US. For the United States: the war boosted nationalism (despite no territorial gain) but devastated Indigenous nations, since their British ally no longer protected their land claims after 1814.
Causes vs effects: Paper 3 examiners reward students who separate causes (impressment, trade, Indigenous alliances, expansionism) from effects (no land changed hands, but identity, nationalism, and Indigenous power all changed a great deal). Don't just narrate the battles.
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Thirty years after the War of 1812, the United States fought Mexico — this time gaining enormous territory. This section covers why the war started and what it changed.
- Manifest Destiny — the belief, widespread in the 1840s US, that Americans were destined by God to expand across the whole continent.
- Annexation of Texas (1845) — the US absorbed the Republic of Texas, which had broken from Mexico in 1836; Mexico still viewed Texas as a rebellious province.
- Border dispute — the US claimed the Rio Grande as the Texas border; Mexico insisted it was the Nueces River, further north.
- President James K. Polk — expansionist president who sent troops into the disputed zone in 1846, provoking a clash that he used to ask Congress for war.
The spark: In April 1846, Mexican and American troops clashed in the disputed Rio Grande borderland. Polk told Congress that Mexico had "shed American blood upon American soil," and Congress declared war — though critics (including a young Abraham Lincoln) argued Polk had provoked the fight.
US forces won a series of victories, including the capture of Mexico City in September 1847 under General Winfield Scott. Mexico, weakened by internal political instability, could not sustain the fight.
Causes
- Manifest Destiny ideology
- Annexation of Texas (1845)
- Disputed Rio Grande/Nueces border
- Polk's deliberate provocation
Effects
- Treaty of Guadalupe Hidalgo (1848)
- Mexico cedes ~55% of its territory (Mexican Cession)
- US gains California, Nevada, Utah, Arizona, New Mexico
- Reignites the US slavery-expansion debate
The Treaty of Guadalupe Hidalgo, 1848: Mexico ceded the Mexican Cession — modern-day California, Nevada, Utah, most of Arizona, and parts of New Mexico, Colorado and Wyoming — in exchange for $15 million. This was one of the largest land transfers in history and made the United States a continental, Pacific-facing power.
Don't forget the domestic fallout: The war's territorial gains forced the US to confront whether new states would allow slavery. The Wilmot Proviso (1846) tried and failed to ban slavery in the new lands, deepening North–South tension well before the Civil War.
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While the US fought external wars, British North America worked through internal political crises that eventually produced a new nation: Canada.
The 1837 Rebellions
- Lower Canada (Quebec) — led by Louis-Joseph Papineau, French-Canadian reformers rebelled against an unelected, British-appointed elite controlling government and land.
- Upper Canada (Ontario) — led by William Lyon Mackenzie, reformers protested the Family Compact, a small clique of officials who dominated government and patronage.
- Common grievance — both rebellions were about the lack of responsible government, not a wish to leave the British Empire entirely.
- Both rebellions were quickly crushed by British troops and loyalist militia in 1837–1838.
The Durham Report (1839)
Lord Durham's diagnosis and remedy: Britain sent Lord Durham to investigate. His 1839 report famously described "two nations warring within the bosom of a single state" (English and French). His two big recommendations: (1) unite Upper and Lower Canada into one Province of Canada to assimilate the French-Canadian population, and (2) grant responsible government so the elected assembly, not London-appointed officials, controlled day-to-day policy.
The Act of Union (1840) merged the two Canadas as recommended. Responsible government was phased in more slowly, achieved in practice by 1848 — a major step toward self-rule, though foreign policy and some powers stayed with Britain.
Challenges to Confederation
- Political deadlock — the united Province of Canada (English-majority Canada West vs French-majority Canada East) was frequently gridlocked, unable to pass legislation.
- Fear of US expansion — after the American Civil War (1861–1865), a battle-hardened US Army and hostile rhetoric worried British North Americans; Fenian raids by Irish-American militants added pressure.
- Economic pressure — Britain ended favourable trade terms and the US cancelled the 1854 Reciprocity Treaty, pushing the colonies to look at uniting their own market.
- Key architects — John A. Macdonald (Canada West) and George-Étienne Cartier (Canada East) built the coalition that pushed Confederation through.
| Conference | Year | Significance |
|---|---|---|
| Charlottetown Conference | 1864 | Maritime union talks widen into a full Confederation proposal |
| Quebec Conference | 1864 | 72 Resolutions drafted — the blueprint for Confederation |
| London Conference | 1866 | Final details settled with the British government |
| British North America Act | 1867 | Creates the Dominion of Canada (Ontario, Quebec, Nova Scotia, New Brunswick) |
Compromises and unresolved issues in the BNA Act: Federalism was the central compromise: strong central government (to satisfy Macdonald, who wanted a unified state) balanced against provincial powers over education, property, and civil law (to protect Quebec's French, Catholic identity). Left unresolved: Indigenous peoples were not consulted at all; women had no political voice; and regional alienation persisted, since the Maritimes felt Central Canada (Ontario/Quebec) would dominate the new Dominion.
Regionalism didn't end in 1867: A strong Paper 3 answer notes that Confederation was a beginning, not a finished project — the west (Manitoba, British Columbia) still had to join, and Maritime resentment ("Confederation was a bad bargain") and Indigenous exclusion remained live issues into the 1870s and beyond.