How many British troops were there?
Around 5,000 soldiers, who will be committed to operations in Iraq, Afghanistan and elsewhere overseas. The British army once had 106 bases and 27,000 troops in Northern Ireland, and had 44 bases here two years ago. It now has fewer than 20 bases and expects to have just 10 by April. The military's longest-running operation officially ended Tuesday. But the symbolic moment came months after the reality - no British troops have been on patrol in the capital, Belfast, for two years.
Why were they there?
They backed up the local police and government, when there was one. Northern Ireland is part of the United Kingdom, along with Great Britain (England, Wales and Scotland). Most of the island gained its independence from Britain after a long struggle, in 1921. The six counties in the northwest - which had a majority Anglo-Irish, mostly Protestant, population - remained part of Britain. An off-shoot of the nationalist Irish Republican Army fought to end British rule and for the rights of the oppressed Catholic Irish. Ultimately, republicans hoped to unite the northern Ulster counties with the Irish republic. The latest violence occurred between 1970 and 1997.
Why so much opposition to British troops if they were combating what sounds like terrorism?
Britain deployed troops in August 1969 to end Protestant mob attacks on Catholic homes in west Belfast and street battles between Catholic civilians and Protestant police in Londonderry, the second-largest city. Most soldiers, welcomed by the Catholic minority, expected to stay for only weeks. Instead, Britain permitted Northern Ireland's Protestant government to control how the forces were used. The newly formed Provisional IRA began launching attacks against police and, eventually, the army, killing its first soldier in 1971. Protestant leaders used the army to impose internment without trial almost exclusively against IRA suspects.
How many people died?
Between 1969 and 1997 more than 3,600 people died in violence related to Northern Ireland, including 709 in the British military, more than 300 Ulster police and reserves, around 400 Republicans, more than 1,200 Catholic civilians and nearly 700 Protestant civilians. Thousands were maimed, physically and emotionally.
The revival of an on-again-off-again peace process. The central goal of the Good Friday peace accord of 1998 - a joint Catholic-Protestant administration that includes the IRA-linked Sinn Fein party - was revived in May and has been operating harmoniously. The other key goal, forging a police force supported on both sides of the community, is more than midway through a 10-year reform program.
Does this mean there is peace in Northern Ireland?
At least temporarily. The future depends on how well the new joint government functions, whether both sides stick to their disarmament agreement and whether the desire for peace outweighs the factions' own interests. None of this settles whether Northern Ireland remains part of Britain or joins the Irish republic. That may eventually be decided by demographics, if Catholics become the majority.
Sources: Associated Press, BBC News
The British army marked a milestone of peacemaking Tuesday as it formally ended its 38-year mission to bolster security in Northern Ireland. Here's a look at some history.