Guy Carleton, 1st Baron Dorchester in the context of "Siege of Fort St. Jean"

United Empire Loyalist (UEL; or simply Loyalist) is an honorific title which was first given by the 1st Lord Dorchester, the governor of Quebec and governor general of the Canadas, to American Loyalists who resettled in British North America during or after the American Revolution. At that time, the demonym Canadian or Canadien was used by the descendants of New France settlers inhabiting the Province of Quebec.

They settled primarily in Nova Scotia and the Province of Quebec. The influx of loyalist settlers resulted in the creation of several new colonies. In 1784, New Brunswick was partitioned from the Colony of Nova Scotia after significant loyalist resettlement around the Bay of Fundy. The influx of loyalist refugees also resulted in the Province of Quebec's division into Lower Canada (present-day Quebec), and Upper Canada (present-day Ontario) in 1791. The Crown gave them land grants of one lot. One lot consisted of 200 acres (81 ha) per person to encourage their resettlement, as the Government wanted to develop the frontier of Upper Canada. This resettlement added many English speakers to the Canadian population. It was the beginning of new waves of immigration that established a predominantly Anglo-Canadian population in the future Canada both west and east of the modern Quebec border.

The invasion of Quebec (June 1775 – October 1776, French: Invasion du Québec) was the first major military initiative by the newly formed Continental Army during the American Revolutionary War. The objective of the campaign was to seize the Province of Quebec (part of modern-day Canada) from Great Britain, and persuade French-speaking Canadiens to join the revolution on the side of the Thirteen Colonies. One expedition left Fort Ticonderoga under Richard Montgomery, besieged and captured Fort Saint-Jean, and very nearly captured British General Guy Carleton when taking Montreal. The other expedition, under Benedict Arnold, left Cambridge, Massachusetts, and traveled with great difficulty through the wilderness of Maine to Quebec City. The two forces joined there, but were defeated at the Battle of Quebec in December 1775.

Montgomery's expedition set out from Fort Ticonderoga in late August, and in mid-September began besieging Fort St. Johns, the main defensive point south of Montreal. After the fort was captured in November, Carleton abandoned Montreal, fleeing to Quebec City. Montgomery took control of Montreal before heading for Quebec, his army much-reduced by expiring enlistments. There he joined Arnold, who had left Cambridge in early September on an arduous trek through the wilderness that left his surviving troops starving and lacking supplies and equipment.

The Battle of Quebec (French: Bataille de Québec) was fought on December 31, 1775, between American Continental Army forces and the British defenders of Quebec City as part of the invasion of Quebec of the American Revolutionary War. The battle was the first major defeat of the war for the Americans, and it came with heavy losses. General Richard Montgomery was killed, Benedict Arnold was wounded, and Daniel Morgan and more than 400 men were taken prisoner. The city's garrison, a motley assortment of regular troops and militia led by Quebec's provincial governor, General Guy Carleton, suffered a small number of casualties.

Montgomery's army had captured Montreal on November 13, and early in December they became one force that was led by Arnold, whose men had made an arduous trek through the wilderness of northern New England. Governor Carleton had escaped from Montreal to Quebec, the Americans' next objective, and last-minute reinforcements arrived to bolster the city's limited defenses before the attacking force's arrival. Concerned that expiring enlistments would reduce his force, Montgomery made the end-of-year attack in a blinding snowstorm to conceal his army's movements. The plan was for separate forces led by Montgomery and Arnold to converge in the lower city before scaling the walls protecting the upper city. Montgomery's force turned back after he was killed by cannon fire early in the battle, but Arnold's force penetrated further into the lower city. Arnold was injured early in the attack, and Morgan led the assault in his place before he became trapped in the lower city and was forced to surrender. Arnold and the Americans maintained an ineffectual blockade of the city until spring, when British reinforcements arrived.