American Invasion of Canada (1775–1776)

Key figures: Benedict Arnold, Richard Montgomery, Guy Carleton, George Washington, William Thompson, John Burgoyne, Charles Carroll

Summary

The American invasion of Canada, spanning September 1775 to June 1776, was an ambitious Continental Army campaign to seize Quebec Province and prevent it from becoming a British staging ground for attacks on the thirteen colonies. Two American forces—one led by General Richard Montgomery via the Richelieu River corridor and another by General Benedict Arnold through the Maine wilderness—converged on Quebec City in late 1775. Montgomery was killed during a night assault on December 31, 1775; subsequent operations, including an ineffectual six-month siege and a crushing defeat at Trois-Rivières (June 8, 1776), forced the Continental Army’s complete withdrawal by mid-June 1776.

Although the campaign failed to capture Canadian territory or secure French-Canadian support for independence, it produced a decisive strategic dividend: American resistance at Quebec and Benedict Arnold’s naval delaying action at Valcour Island (October 11, 1776) prevented British General Guy Carleton from launching a simultaneous invasion down the Hudson Valley that year. This bought the Continental Army critical time, enabling the transformative American victory at Saratoga (September–October 1777) and the subsequent French alliance that altered the war’s entire trajectory. See also French Alliance (1778).

Strategic Context

Why Canada?

The Continental Congress authorized the invasion in June 1775, months before open warfare had broadened into full revolution. The strategic logic was threefold:

1. Denial: Quebec Province gave Britain a ready-made northern base from which a powerful army could drive down the Lake Champlain–Hudson River corridor and sever New England from the middle colonies—a scenario American commanders feared above all others. Capturing the province would eliminate this threat.
2. Recruitment: An estimated 70,000–90,000 French Canadians (Canadiens) lived under British rule after the 1763 Treaty of Paris. Congress hoped they would welcome liberation from British administration, provide men and supplies, and join the union as a fourteenth state.
3. Prestige: Early military success was needed to consolidate domestic support and potentially attract foreign attention. A captured Quebec City—the linchpin of British North America—would signal that the rebellion was a serious national enterprise.

Washington endorsed the plan but could spare few troops, as the army besieging Boston was already under-resourced. He authorized only two expeditionary columns, neither large enough for a conventional siege without Canadian cooperation. The political dimension—winning Canadien loyalty—was therefore as important as the military one.

British Vulnerability

At the campaign’s outset in autumn 1775, British regulars in Quebec Province numbered fewer than 1,000, scattered across forts and garrison posts. Governor and commander Guy Carleton had urgently requested reinforcements from London but received none before winter closed the St. Lawrence River to shipping. Carleton’s only realistic option was to concentrate his forces inside the fortified walls of Quebec City and wait—which is precisely what he did. His masterly defensive strategy ultimately turned the campaign’s balance. See also British Naval Operations in 1776 for the broader context of British North American strategy coordinated under Lord George Germain.

The Two-Pronged Advance (September–November 1775)

Montgomery’s Column

General Richard Montgomery, an Anglo-Irish professional soldier who had served in the Seven Years’ War before emigrating to New York, commanded roughly 1,700 men moving north from Fort Ticonderoga along the Richelieu River. His force methodically reduced British strongholds:

• Fort St. Jean: After a 55-day siege (September 5–November 2, 1775), the garrison of ~500 surrendered. The prolonged siege consumed critical autumn weeks that Montgomery desperately needed before winter.
• Montreal: Carleton abandoned the city without serious resistance on November 11, 1775, giving Montgomery not only a strategic prize but also badly needed supplies and artillery.
• Junction at Quebec: Montgomery arrived outside Quebec City in early December with approximately 300 men—disease, expired enlistments, and detachments having stripped his force to a fraction of its original strength.

Arnold’s Wilderness March

Simultaneously, Colonel Benedict Arnold led approximately 1,100 men from Cambridge, Massachusetts, beginning September 19, 1775. Arnold’s route—up the Kennebec River, across the Height of Land, and down the Chaudière River to Quebec—was one of the most grueling marches in American military history.

• Distance and terrain: The expedition covered roughly 350 miles through unmapped Maine wilderness, crossing three major watersheds and navigating impassable bogs, waterfalls, and swamps.
• Catastrophic attrition: Defective bateaux (flat-bottomed boats) rotted and sank, destroying provisions. One full company (~200 men) under Colonel Roger Enos turned back without authorization. By the time Arnold’s force reached Quebec in early November, only about 600 men had survived the march fit for duty.
• Hunger and cold: Men consumed candle wax, leather, and boiled cartridge cases. Several died of starvation or exposure. The expedition’s hardship became legendary—Washington later called it one of the most remarkable marches in history.
• Strategic achievement: Despite the losses, Arnold’s force reached the south bank of the St. Lawrence and crossed in late October–early November 1775, appearing before Quebec City and achieving complete strategic surprise. Carleton had believed the route impassable.

By early December 1775, both columns had united outside Quebec City with a combined effective strength of approximately 900–1,000 men against Carleton’s garrison of roughly 1,200 defenders sheltered behind the formidable stone walls of one of North America’s most heavily fortified cities.

The Assault on Quebec City (December 31, 1775)

After weeks of fruitless siege—American artillery was insufficient to breach Quebec’s walls, and smallpox was spreading through the camp—Montgomery and Arnold resolved on a night assault during a heavy snowstorm on December 31, 1775. The timing was driven partly by the expiration of many soldiers’ enlistment terms on January 1, 1776.

The plan involved two simultaneous attacks on Quebec’s lower town while diversionary forces demonstrated against the upper town gates. Execution was disastrously poor:

• Montgomery’s attack: Advancing along the St. Lawrence River shore with approximately 300 men, Montgomery was killed in the first British barrage—a cannon discharge at nearly point-blank range struck him and two aides dead, and his column, leaderless, retreated immediately.
• Arnold’s attack: Arnold’s larger force briefly penetrated the lower town, but Arnold himself was struck in the leg by a musket ball and had to be carried from the field. Command passed to Captain Daniel Morgan, whose men fought through narrow streets before being surrounded and forced to surrender—approximately 400 prisoners.
• Casualties: American losses were roughly 60 killed or wounded and more than 400 captured; British losses were minimal (approximately 5 killed, 13 wounded).

The assault’s failure transformed the campaign from an offensive operation into an indefinite siege. Arnold, still limping from his wound, organized the remaining American forces to maintain a loose blockade of the city through the bitter winter of 1776. Smallpox ravaged the besieging army; by spring, the force had been repeatedly reinforced from the south but never recovered its effectiveness.

The French-Canadian Response

A central premise of the invasion was that Canadiens would actively join or at least supply the American cause. This expectation was almost entirely unrealized:

• The Quebec Act (1774): Britain’s Quebec Act had guaranteed French Canadians religious freedom for Roman Catholicism, preserved French civil law, and extended the province’s boundaries. While American patriots condemned the Act as one of the “Intolerable Acts,” most Canadiens viewed it as a generous accommodation—the Catholic clergy, in particular, urged neutrality or loyalty to the Crown.
• Limited recruitment: Congress sent Charles Carroll (a Maryland Catholic), Benjamin Franklin, and Samuel Chase on a diplomatic mission to Montreal in spring 1776. The mission failed entirely; Franklin, already 70 and ill, returned early. The Canadiens provided some supplies to American forces when paid in hard currency, but relatively few individuals volunteered for military service.
• Alienation: American troops’ appropriation of supplies without payment, destruction of property, and conflicts with Catholic habitants deepened hostility. By May 1776, many Canadiens who had initially been neutral actively assisted British forces.

Joseph Brant’s mission to London in 1775–1776 and the Iroquois Confederacy’s alignment with Britain added a further dimension: see Joseph Brant (Thayendanegea) for how Britain secured critical indigenous allies along the northern frontier.

The 1776 Collapse

Spring 1776 brought catastrophic deterioration for the American position:

• British reinforcements: In May 1776, approximately 10,000 British and German reinforcements (including Hessian regiments) arrived at Quebec City by sea, commanded by General John Burgoyne. See Hessian Troops in the American Revolution for the broader context of German auxiliary forces in the British war effort.
• Trois-Rivières (June 8, 1776): General William Thompson led approximately 2,000 American troops in an attack on the town of Trois-Rivières, unaware that British regulars had arrived in large numbers. Thompson’s force was routed; 236 Americans were taken prisoner, including Thompson himself.
• Complete withdrawal: The Continental Army retreated in stages from Sorel to St. Johns to Crown Point on Lake Champlain. By June 18, 1776, no American troops remained on Canadian soil. The withdrawal was chaotic—men were abandoned, supplies destroyed, and smallpox carriers marched alongside healthy troops, spreading disease southward.

The contrast with the 1776 New York campaign was stark: as the American army collapsed in Canada, General Howe was preparing to descend on New York with a massive amphibious force. See Battle of Long Island for the summer 1776 crisis that followed.

Lake Champlain and Valcour Island (October 1776)

The retreat from Canada was not the end of Benedict Arnold’s contribution to the northern theater. Understanding that Britain needed naval control of Lake Champlain before any overland advance southward could proceed, Arnold undertook a remarkable improvised shipbuilding program at Skenesborough (modern Whitehall, New York) during summer 1776.

• Fleet composition: Arnold assembled a flotilla of 15 vessels, most built from green timber by carpenters with minimal naval experience. The fleet included the flagship schooner Royal Savage, the galley Congress (Arnold’s personal command), and several smaller gunboats.
• Battle of Valcour Island (October 11, 1776): The British fleet under Commodore Thomas Pringle attacked Arnold’s fleet near Valcour Island on Lake Champlain. After an all-day engagement, American losses were severe: 11 vessels destroyed or captured, approximately 200 casualties. Arnold escaped south with surviving vessels, which he deliberately beached and burned to prevent capture.
• Strategic achievement: Though a tactical defeat, the battle forced Carleton to spend weeks consolidating before any southward advance. By the time he reached Crown Point, the lateness of the season made a full campaign toward Fort Ticonderoga impossible. Carleton returned to winter quarters in Canada, and the decisive British invasion did not come until 1777 under Burgoyne.

Aftermath and Strategic Legacy

The failure in Canada cast a long shadow over American strategy but contained seeds of its ultimate reversal:

• Saratoga (1777): Burgoyne’s 1777 invasion from Canada—the assault that the 1776 campaign’s delays had postponed—ended in catastrophic British defeat at Saratoga (September–October 1777). The American victory there directly brought France into the war as an open ally, transforming it from a colonial rebellion into a global conflict. See French Alliance (1778) for the diplomatic consequences.
• Benedict Arnold’s trajectory: The Quebec campaign was the making and partial breaking of Arnold’s reputation. He won widespread praise for his wilderness march and his Lake Champlain defense, and was promoted to Major General. Yet passed over for promotion in early 1777 due to Congressional politics, his resentment deepened—a trajectory that would eventually lead to his 1780 treason, the very year after Saratoga had sealed the Franco-American alliance he had helped make possible.
• Lessons for command: The campaign demonstrated both the potential and the limits of combined-arms amphibious–overland operations with under-resourced, short-enlistment armies. Washington incorporated its lessons into his emphasis on longer enlistments and professional training in the reorganized Continental Army.
• Canada’s future: The invasion’s failure ensured Quebec Province remained under British rule. The influx of Loyalist refugees after 1783 and the Constitution Act of 1791 (which divided Quebec into Upper and Lower Canada) shaped the country that would eventually become Canada.

Key Figures

Sources

• Invasion of Quebec (1775) — Wikipedia article detailing the campaign timeline, commanders, and outcomes.
• Benedict Arnold — Wikipedia biography covering Arnold’s role in the Quebec campaign, Lake Champlain command, and subsequent career.
• Battle of Valcour Island — Wikipedia military history article on the October 1776 naval engagement, fleet composition, and strategic consequences.
• Battle of Trois-Rivières — Wikipedia military history article on the June 8, 1776 British victory and American prisoner losses.
• Saratoga Campaign — Wikipedia article on the 1777 campaign and its strategic consequences, including context on 1776 Canadian operations.
• Quebec Act — Wikipedia article on the 1774 legislation that shaped French-Canadian loyalty during the invasion.
• Arnold’s Expedition to Quebec — Wikipedia article detailing the wilderness march route, attrition, and logistical failures.