Northern Ireland is a part of the United Kingdom in the north-east of the island of Ireland. Northern Ireland shares a border with the Republic of Ireland to the south and west. As of 2011, its population was 1,810,863, constituting about 30% of the island's total population and about 3% of the population of the United Kingdom. Since the signing of the Good Friday Agreement in 1998, Northern Ireland is largely self-governing. According to the agreement, Northern Ireland co-operates with the rest of Ireland – from which it was partitioned in 1921 – on some policy areas, while other areas are reserved for the Government of the United Kingdom, though the Republic of Ireland "may put forward views and proposals". Northern Ireland was for many years the site of a violent and bitter inter-communal conflict which was caused by divisions between nationalists, who see themselves as Irish and are predominantly Roman Catholic, and unionists, who see themselves as British and are predominantly Protestant. Unionists want Northern Ireland to remain as a part of the United Kingdom, while nationalists want reunification with the rest of Ireland, independent of British rule. Since 1998, most of the paramilitary groups involved in the Troubles have ceased their armed campaigns. Northern Ireland has traditionally been the most industrialised region of the island. After declining as a result of political and social turmoil in the second half of the 20th century, it has grown significantly since the 1990s. This is in part due to a "peace dividend" and in part due to links and increased trade with the Republic of Ireland. Prominent artists and sports persons from Northern Ireland include Van Morrison, Rory McIlroy and George Best. Others from that part of the island prefer to define themselves as Irish, e.g. Seamus Heaney and Liam Neeson. Cultural links between Northern Ireland, the rest of Ireland and the rest of the UK are complex, with Northern Ireland sharing both the culture of Ireland and the culture of the United Kingdom. In most sports the island of Ireland fields a single team, a notable exception being association football. Northern Ireland competes separately at the Commonwealth Games and athletes from Northern Ireland may compete for either Great Britain or Ireland at the Olympic Games.