The Troubles in the context of "Good Friday Agreement"

The impact of Brexit on the Irish border and its adjacent polities involves changes in trade, customs, immigration checks, local economies, services, recognition of qualifications, medical cooperation, and other matters, as it is the only land border between the United Kingdom and the European Union.

After the UK Parliament voted to leave the European Union, all parties said that they want to avoid a hard border in Ireland, due particularly to the border's historically sensitive nature. Border issues were one of three areas of focused negotiation in the Withdrawal Agreement. Following the United Kingdom's exit from the European Union on 31 January 2020, this border is also the frontier between the EU and an external country.

Ireland (Irish: Éire [ˈeːɾʲə] ), also known as the Republic of Ireland (Poblacht na hÉireann), is a country in Northwestern Europe. It consists of 26 of the 32 counties of the island of Ireland, with a population of about 5.4 million. Its capital and largest city is Dublin, on the eastern side of the island, with a population of over 1.5 million. The sovereign state shares its only land border with Northern Ireland, which is part of the United Kingdom. It is otherwise surrounded by the Atlantic Ocean, with the Celtic Sea to the south, St George's Channel to the south-east and the Irish Sea to the east. It is a unitary, parliamentary republic. The legislature, the Oireachtas, consists of a lower house, Dáil Éireann; an upper house, Seanad Éireann; and an elected president (Uachtarán) who serves as the largely ceremonial head of state, but with some important powers and duties. The head of government is the Taoiseach (prime minister, lit. 'chief'), elected by the Dáil and appointed by the president, who appoints other government ministers.

The Irish Free State was created with Dominion status in 1922, following the Anglo-Irish Treaty. In 1937, a new constitution was adopted, in which the state was named "Ireland" and effectively became a republic, with an elected non-executive president. It was officially declared a republic in 1949, following The Republic of Ireland Act 1948. Ireland became a member of the United Nations in 1955. It joined the European Communities (EC), the predecessor of the European Union (EU), in 1973. The state had no formal relations with Northern Ireland for most of the 20th century, but the 1980s and 1990s saw the British and Irish governments working with Northern Irish parties to resolve the conflict that had become known as the Troubles. Since the signing of the Good Friday Agreement in 1998, the Irish government and Northern Irish government have co-operated on a number of policy areas under the North/South Ministerial Council created by the Agreement.

The Government of Ireland Act 1920 (10 & 11 Geo. 5. c. 67) was an act of the Parliament of the United Kingdom. The Act's long title was "An Act to provide for the better government of Ireland"; it is also known as the Fourth Home Rule Bill or (inaccurately) as the Fourth Home Rule Act and informally known as the Partition Act. The Act was intended to partition Ireland into two self-governing polities: the six north-eastern counties were to form "Northern Ireland", while the larger part of the country was to form "Southern Ireland". Both territories were to remain part of the United Kingdom of Great Britain and Ireland and provision was made for their future reunification through a Council of Ireland. The Act was passed by the British Parliament in November 1920, received royal assent in December and came into force on 3 May 1921.

The smaller Northern Ireland was duly created with a devolved government and remained in the UK. The larger Southern Ireland was not recognised by most of its citizens, who instead recognised the self-declared Irish Republic in the ongoing Irish War of Independence. The conflict resulted in the Anglo-Irish Treaty in December 1921. Under the treaty, Ireland would leave the UK (with the option for Northern Ireland to opt out and remain in the UK, which it immediately did) in December 1922 and become the Irish Free State, which would later evolve into today's Republic of Ireland. The institutions set up under this Act for Northern Ireland continued to function until they were suspended by the British parliament in 1972 as a consequence of the Troubles.

Ulster Protestants are an ethnoreligious group in the Irish province of Ulster, where they make up about 43.5% of the population. Most Ulster Protestants are descendants of settlers who arrived from Great Britain in the early 17th century Ulster Plantation. This was the settlement of the Gaelic, Catholic province of Ulster by Scots and English speaking Protestants, mostly from the Scottish Lowlands and Northern England. Many more Scottish Protestant migrants arrived in Ulster in the late 17th century. Those who came from Scotland were mostly Presbyterians, while those from England were mostly Anglicans (see Church of Ireland). There is also a small Methodist community and the Methodist Church in Ireland dates to John Wesley's visit to Ulster in 1752. Although most Ulster Protestants descend from Lowland Scottish people (some of whose descendants consider themselves Ulster Scots), many descend from English, and to a lesser extent, from Irish, Welsh and Huguenots.

Since the 17th century, sectarian and political divisions between Ulster Protestants and Irish Catholics have played a major role in the history of Ulster, and of Ireland as a whole. It has led to bouts of violence and political upheaval, notably in the Irish Confederate Wars, the Cromwellian conquest of Ireland, the Williamite War, the Armagh disturbances, Irish Rebellion of 1798, the Irish revolutionary period, and the Troubles. Today, the vast majority of Ulster Protestants live in Northern Ireland, which was created in 1921 to have an Ulster Protestant majority, and in the east of County Donegal. Politically, most are unionists, who have an Ulster British identity and want Northern Ireland to remain part of the United Kingdom.

United Ireland (Irish: Éire Aontaithe), also referred to as Irish reunification or a New Ireland, is the proposition that all of Ireland should be a single sovereign state. At present, the island is divided politically: the sovereign state of Ireland (legally described also as the Republic of Ireland) has jurisdiction over the majority of Ireland, while Northern Ireland, which lies entirely within (but consists of only 6 of 9 counties of) the Irish province of Ulster, is part of the United Kingdom. Achieving a united Ireland is a central tenet of Irish nationalism and Republicanism, particularly of both mainstream and dissident republican political and paramilitary organisations. Unionists support Northern Ireland remaining part of the United Kingdom and oppose Irish unification.

Ireland has been partitioned since May 1921, when the Government of Ireland Act 1920 came into effect, creating two separate jurisdictions—Southern Ireland and Northern Ireland—within the United Kingdom. Southern Ireland never fully functioned and was soon replaced by the Irish Free State in 1922, which became independent, while Northern Ireland opted to remain part of the UK. The Anglo-Irish Treaty, which led to the establishment in December 1922 of a dominion called the Irish Free State, recognised partition, but this was opposed by anti-Treaty republicans. When the anti-Treaty Fianna Fáil party came to power in the 1930s, it adopted a new constitution which claimed sovereignty over the entire island. The Irish Republican Army (IRA) had a united Ireland as its goal during the conflict with British security forces and loyalist paramilitaries from the 1960s to the 1990s known as The Troubles. The Good Friday Agreement signed in 1998, which ended the conflict, acknowledged the legitimacy of the desire for a united Ireland, while declaring that it could be achieved only with the consent of a majority of the people of both jurisdictions on the island, and providing a mechanism for ascertaining this in certain circumstances.

The Provisional Irish Republican Army (Provisional IRA), officially known as the Irish Republican Army (IRA; Irish: Óglaigh na hÉireann) and informally known as the Provos, was an Irish republican paramilitary force that sought to end British rule in Northern Ireland, facilitate Irish reunification and bring about an independent republic encompassing all of Ireland. It was the most active republican paramilitary group during the Troubles. It argued that the all-island Irish Republic continued to exist, and it saw itself as that state's army, the sole legitimate successor to the original IRA from the Irish War of Independence. It was designated a terrorist organisation in the United Kingdom and an unlawful organisation in the Republic of Ireland, both of whose authority it rejected.

The Provisional IRA emerged in December 1969, due to a split within the previous incarnation of the IRA and the broader Irish republican movement. It was initially the minority faction in the split compared to the Official IRA but became the dominant faction by 1972. The Troubles had begun shortly before when a largely Catholic, nonviolent civil rights campaign was met with violence from both Ulster loyalists and the Royal Ulster Constabulary (RUC), culminating in the August 1969 riots and deployment of British soldiers. The IRA initially focused on defence of Catholic areas, but it began an offensive campaign in 1970 that was aided by external sources, including Irish diaspora communities within the Anglosphere, and the Palestine Liberation Organization and Libyan leader Muammar Gaddafi. It used guerrilla tactics against the British Army and RUC in both rural and urban areas, and carried out a bombing campaign in Northern Ireland and England against military, political and economic targets, and British military targets in mainland Europe. They also targeted civilian contractors to the British security forces. The IRA's armed campaign, primarily in Northern Ireland but also in England and mainland Europe, killed over 1,700 people, including roughly 1,000 members of the British security forces and 500–644 civilians.

The Parliament of Northern Ireland was the home rule legislature of Northern Ireland, created under the Government of Ireland Act 1920, which sat from 7 June 1921 to 30 March 1972, when it was suspended because of its inability to restore order during the Troubles, resulting in the introduction of direct rule. It was abolished under the Northern Ireland Constitution Act 1973.

The Parliament of Northern Ireland was bicameral, consisting of a House of Commons with 52 seats, and an indirectly elected Senate with 26 seats. The Sovereign was represented by the governor (initially by the Lord Lieutenant), who granted royal assent to Acts of Parliament in Northern Ireland, but executive power rested with the prime minister, the leader of the largest party in the House of Commons.

Waterboarding or controlled drowning is a form of torture in which water is poured over a cloth covering the face and breathing passages of an immobilized captive, causing the person to experience the sensation of drowning. In the most common method of waterboarding, the captive's face is covered with cloth or some other thin material and immobilized on their back at an incline of 10 to 20 degrees. Torturers pour water onto the face over the breathing passages, causing an almost immediate gag reflex and creating a drowning sensation for the captive. Normally, water is poured intermittently to prevent death; however, if the water is poured uninterruptedly it will lead to death by asphyxia. Waterboarding can cause extreme pain, damage to lungs, brain damage from oxygen deprivation, other physical injuries including broken bones due to struggling against restraints, and lasting psychological damage. Adverse physical effects can last for months, and psychological effects for years. The term "water board torture" appeared in press reports as early as 1976.

Waterboarding has been used in diverse places and at various points in history, including the Spanish and Flemish Inquisitions, by the United States military during the Philippine–American War, by Japanese and German officials during World War II, by the French in the Algerian War, by the U.S. during the Vietnam War and the war on terror, by the Pinochet regime in Chile, by the Khmer Rouge in Cambodia, by British security forces during the Troubles, and by South African police during the Apartheid era. Historically, waterboarding has been viewed as an especially severe form of torture.