Guy Carleton, 1st Baron Dorchester in the context of Samuel Birch (military officer)

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.

The siege of Fort St. Jean (September 17 – November 3, 1775 French: Siège du Fort Saint-Jean) was conducted by American Brigadier General Richard Montgomery on the town and fort of Saint-Jean, also called St. John, St. Johns, or St. John's, in the British province of Quebec during the American Revolutionary War. The siege lasted from September 17 to November 3, 1775.

After several false starts in early September, the Continental Army established a siege around Fort St. Jean. Beset by illness, bad weather, and logistical problems, they established mortar batteries that were able to penetrate into the interior of the fort, but the defenders, who were well-supplied with munitions, but not food and other supplies, persisted in their defence, believing the siege would be broken by forces from Montreal under General Guy Carleton. On October 18, the nearby Fort Chambly fell, and on October 30, an attempt at relief by Carleton was thwarted. When word of this made its way to St. Jean's defenders, combined with a new battery opening fire on the fort, the fort's defenders capitulated, surrendering on November 3.

Baron Dorchester was a title that was created twice in British history, once in the Peerage of Great Britain and once in the Peerage of the United Kingdom. The first creation came in the Peerage of Great Britain on 21 August 1786 when the soldier and administrator Sir Guy Carleton was made Lord Dorchester, Baron of Dorchester, in the County of Oxford. He was succeeded by his grandson, the second Baron. He was the only son of the Hon. Christopher Carleton, third son of the first Baron. The second Baron died unmarried at an early age and was succeeded by his first cousin, the third Baron. He was the only son of the Hon. George Carleton, fourth son of the first Baron. He had no sons and was succeeded by his first cousin, the fourth Baron. He was the only son of the Reverend and Hon. Richard Carleton, seventh son of the first Baron. The fourth Baron was a Colonel in the Coldstream Guards. He was childless, and the title became extinct upon his death on 30 November 1897.

The title was revived on 2 August 1899 when the Honourable Henrietta Anne Carleton was made Baroness Dorchester, of Dorchester, in the County of Oxford, in the Peerage of the United Kingdom. She was the elder daughter of the third Baron of the first creation. She was the wife of, firstly, Francis Paynton Pigott and, secondly, of Major-General Richard Langford Leir. In 1899, she assumed by Royal licence the surname of Carleton. She was succeeded by her son from her first marriage, the second Baron. He was a soldier and fought in the Second Boer War and the First World War. He had two daughters but no sons, and on his death in 1963, the title became extinct for the second time.

The office of Commander-in-Chief, North America was a military position of the British Army. Established in 1755 in the early years of the Seven Years' War, holders of the post were generally responsible for land-based military personnel and activities in and around those parts of North America that Great Britain either controlled or contested. The post continued to exist until 1775, when Lieutenant-General Thomas Gage, the last holder of the post, was replaced early in the American War of Independence. The post's responsibilities were then divided: Major-General William Howe became Commander-in-Chief, America, responsible for British troops from West Florida to Newfoundland, and General Guy Carleton became Commander-in-Chief, Quebec, responsible for the defence of the Province of Quebec.

This division of responsibility persisted after American independence and the loss of East and West Florida in the Treaty of Paris (1783). One officer was given the posting for Quebec, which later became the Commander-in-Chief of The Canadas when Quebec was divided into Upper and Lower Canada, while another officer was posted to Halifax with responsibility for military matters in the maritime provinces.

The Book of Negroes is a document created by Brigadier General Samuel Birch, under the direction of Sir Guy Carleton, that records names and descriptions of 3,000 Black Loyalists, enslaved Africans who escaped to the British lines during the American Revolution and were evacuated to points in Nova Scotia as free people of colour.