The Troubles

During the twentieth century, there have been two periods of unrest in Ireland, which have become known as the Troubles. The first was the Irish War of Independence, a guerrilla campaign conducted by the Irish Republican Army (often called the Old IRA to distinguish it from the later IRA) against the British government in Ireland from 1919 until the truce in 1921. The peace talks led to the Anglo-Irish Treaty (1921), which allowed the mostly Protestant Northern Ireland to opt out of the mostly Catholic Irish Free State. Northern Ireland did so and became part of the United Kingdom of Great Britain and Ireland. The Irish Free State, that part of Ireland that declared itself independent from Britain, was named the Republic of Ireland, or simply Ireland.

The second period of Troubles centered on the violence involving paramilitary organizations such as the IRA, the Royal Ulster Constabulary (RUC, the...