In general loyalism refers to an individual's allegiance toward an established government, political party, or sovereign, especially during times of war and revolt. The most common usage of the term refers to loyalty to the British Crown, especially to opponents of the American Revolution and those exiles who went to Canada.
The term loyalist was also used during the Spanish Civil War, applying to Republicans who remained loyal to the Spanish Republic against Franco's "Nationalists."
In North America, the term loyalist characterised colonists who rejected the American Revolution in favour of remaining within the British Empire. American loyalists included royal officials, Anglican clergymen, wealthy merchants with ties to London, demobilised British soldiers, and recent arrivals (especially from Scotland), as well as many ordinary colonists who were conservative by nature and/or felt that the protection of Britain was needed. Colonists with loyalist sympathies accounted for an estimated 15% to 20% of the white colonial population of the day, compared with those described as "Patriots", who accounted for about 40-50% of the population. This high level of political polarisation leads historians to argue that the American Revolution was as much a civil war as it was a war of independence from the British Crown.
British military strategy during the American Revolution relied on mobilising loyalist soldiers throughout the Thirteen Colonies. Throughout the war, the British military formed over 100 loyalist line regiments whose strength totaled 19,000 of which 9,700 served most at one time. Including militia and marine forces more than 50,000 served. The Patriots used tactics such as property confiscation to suppress loyalism and drive active loyalists away. After the war, approximately 80-90% of the Loyalists stayed in the new United States, and adapted to the new conditions and changes of a republic. However, over 70,000 Loyalists sought refuge elsewhere in Lower Canada, Quebec (divided in 1791 into what is now Quebec and Ontario), the Maritime provinces, Jamaica, the Bahamas and in Britain, often with financial help from the Crown. Most re-settled in the British North American Provinces of Quebec and Nova Scotia in present-day Canada. This migration also included Native American loyalists such as Mohawk leader Joseph Brant, the "Black Loyalists" – former slaves who had joined the British cause in exchange for their freedom, and Anabaptist loyalists (Mennonites). These Loyalists were the founders of modern English-speaking Canada, and many of their descendants still identify themselves with the nominal hereditary title "UEL" (United Empire Loyalist) today.