Young people have thrown bricks, fireworks and petrol bombs at police and burned hijacked cars and buses during a week of violence in the streets. Northern Ireland. Police responded with rubber bullets and water cannons.

The streets were calmer on Friday night, as community leaders asked for calm after the death of Prince Philip, the husband of Queen Elizabeth II, 99 years old. But a small group of youths pelted police with objects and set fire to cars during the sporadic outbreak in Belfast.

The chaotic scenes have evoked the memory of decades of the Catholic-Protestant conflict, known as The Troubles. The 1998 peace deal ended large-scale violence but did not resolve deep-rooted tensions in Northern Ireland.

A glimpse of the backdrop of the new violence:

WHY NORTH IRELAND CONTEST LAND?

Geographically, Northern Ireland is a part of Ireland. Politically, it’s part of Great Britain.

Ireland, long dominated by its larger neighbors, broke free some 100 years ago after centuries of colonization and uneasy unity. Twenty-six of its 32 counties are independent states with a Roman Catholic majority. The six counties in the north, which have a Protestant majority, remain British.

Northern Ireland’s Catholic minority experiences discrimination in employment, housing, and other areas of the Protestant-run state. In the 1960s, the Catholic civil rights movement demanded change, but faced a strong response from the government and police. Some people, both Catholic and Protestant, formed armed groups that escalated the violence by bombing and shooting.

The British Army was deployed in 1969, initially to keep the peace. The situation deteriorated into conflict between the militant republican Ireland who wanted to unite with the south, loyalist paramilitaries trying to keep Northern Ireland into Britain, and British troops.

During the three decades of conflict more than 3,600 people, most of them civilians, died in bombings and shootings. Most of these were in Northern Ireland, although the Irish Republican Army also detonated bombs in London and other British cities.

HOW DOES THE CONFLICT END?

In the 1990s, after secret talks and with the help of diplomatic efforts by Ireland, Britain and the United States, the fighters reached a peace agreement. The 1998 Good Friday deal saw paramilitaries lay down their weapons and establish a Catholic-Protestant power-sharing government for Northern Ireland. The question of Northern Ireland’s final status was postponed: it would remain with Britain as long as it was the wish of the majority, but a future referendum on reunification was not ruled out.

While the peace has largely persisted, small groups of the Irish Republican Army have carried out occasional attacks on security forces, and there has been sectarian street violence.

Politically, power-sharing arrangements have had times of success and failure. The Belfast administration collapsed in January 2017 due to a failed green energy project. It remained suspended for more than two years amid a rift between British trade unions and Irish nationalist parties over cultural and political issues, including the status of the Irish language. The Northern Irish government returns to work in early 2020, but there is still deep mistrust on both sides.

HOW DOES BREXIT HAVE COMPLICATED THINGS?

Northern Ireland has been called the problem child of Brexit, Britain’s divorce from the European Union. As the only part of the UK that has borders with the European Union country, Ireland, it is the toughest issue to resolve after Britain voted narrowly in 2016 to leave the 27-nation bloc.

Ireland’s open borders, where people and goods flow freely, underpin the peace process, allowing people in Northern Ireland to feel at home in Ireland and Great Britain.

The UK Conservative government’s insistence on a tough Brexit that takes the country out of the EU economic order means the creation of new barriers and trade checks. Both the UK and the EU agree that the border should not be in Ireland because of the risks this will pose to the peace process. The alternative is to place it, metaphorically, in the Irish Sea between Northern Ireland and the rest of Great Britain.

The arrangement has worried British union members, who say it weakens Northern Ireland’s place in Britain and could increase calls for Irish reunification.

WHY IS VIOLENCE REMOVED NOW?

The violence was mostly in Protestant areas in and around Belfast and Northern Ireland’s second city, London, although the disturbance had spread to Catholic circles.

Britain left the EU’s economic arms on December 31, and new trade arrangements quickly irked Northern Irish union members who wanted to stay in the UK. Initial trade disruptions, exacerbated by the coronavirus pandemic, left several supermarket shelves empty, sparking alarms. Border staff temporarily withdrew from a Northern Irish port in February after threatening graffiti appeared to target port workers.

There is anger that British Prime Minister Boris Johnson, long insisting there will be no new checks on trade as a result of Brexit, has underestimated the scale of change wrought by leaving the EU. Some British loyalist communities in Northern Ireland feel their identity is under threat.

Many loyalists believe that, de facto, Northern Ireland is no longer part of Britain as it used to be, Ulster University politics professor Henry Patterson told Sky News.

(Only the title and image of this report may have been reworked by Business Standards staff; other content was generated automatically from syndicated feeds.)