Northern Ireland ( ;
Ulster Scots: ) is a
constituent unit of the
United Kingdom of Great Britain and Northern Ireland in the northeast of the island of
Ireland. It is variously described as a
country,
province,
region, or "part" of the United Kingdom, amongst other terms. 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".