The British never officially recognized the armed conflict in Northern Ireland as a war. The term “Troubles” is an understated reference to the 30-year conflict in which paramilitaries and State police and military forces fought over the constitutional status of Northern Ireland. The Troubles had ethnic and religious dimensions. Republicans, often Catholics, wanted to terminate British control and unite the North with the Republic that had won independence in 1921. Loyalists, often Protestants, wanted to remain British by definition, governed with the United Kingdom rather than the Republic. The violence was largely working-class. What started as an armed struggle eventually became a diplomatic and political struggle that terminated in 1998 with the Good Friday Agreement, which ushered in a peace process and committed to future votes on Northern Irish national affiliation. Majority rule in these referendum votes would determine whether the country remains in the United Kingdom or joins the Republic as a united Ireland.

Both republicans and loyalists formed paramilitaries, armed combat entities structured and trained similar to an army, during the Troubles. While these organizations had internal promotion and disciplinary proceedings, formal leadership, and engaged in diplomatic efforts, they remained independent from the official armed forces recognized in Northern Ireland and England.