<Li> ^ + 44 is always followed by 28 when calling landlines . The code is 028 within the UK and 048 from the Republic of Ireland where it is treated as a domestic call . </Li> <P> Northern Ireland (Irish: Tuaisceart Éireann (ˈt̪ɣuəʃcəɾɣt̪ɣ ˈeːɾjən̪ɣ) (listen); Ulster - Scots: Norlin Airlann) is a part of the United Kingdom in the north - east of the island of Ireland, variously described as a country, province or region . Northern Ireland shares a border to the south and west with the Republic of Ireland . In 2011, its population was 1,810,863, constituting about 30% of the island's total population and about 3% of the UK's population . Established by the Northern Ireland Act 1998 as part of the Good Friday Agreement, the Northern Ireland Assembly holds responsibility for a range of devolved policy matters, while other areas are reserved for the British government . Northern Ireland co-operates with the Republic of Ireland in some areas, and the Agreement granted the Republic the ability to "put forward views and proposals" with "determined efforts to resolve disagreements between the two governments". </P> <P> Northern Ireland was created in 1921, when Ireland was partitioned between Northern Ireland and Southern Ireland by the Government of Ireland Act 1920 . Unlike Southern Ireland, which would become the Irish Free State in 1922, the majority of Northern Ireland's population were unionists, who wanted to remain within the United Kingdom . Most of these were the Protestant descendants of colonists from Great Britain . However, a significant minority, mostly Catholics, were nationalists who wanted a united Ireland independent of British rule . Today, the former generally see themselves as British and the latter generally see themselves as Irish, while a distinct Northern Irish or Ulster identity is claimed both by a large minority of Catholics and Protestants and by many of those who are non-aligned . </P> <P> For most of the 20th century, when it came into existence, Northern Ireland was marked by discrimination and hostility between these two sides in what First Minister of Northern Ireland David Trimble called a "cold house" for Catholics . In the late 1960s, conflict between state forces and chiefly Protestant unionists on the one hand, and chiefly Catholic nationalists on the other, erupted into three decades of violence known as the Troubles, which claimed over 3,500 lives and caused over 50,000 casualties . The 1998 Good Friday Agreement was a major step in the peace process, including the decommissioning of weapons, although sectarianism and religious segregation still remain major social problems, and sporadic violence has continued . </P>

Why is northern ireland part of the united kingdom
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