/div>Country, western Europe, occupying the greater part of the island of Ireland west of Great Britain. Area: 27,133 sq mi (70,273 sq km). Population: (2009 est.) 4,553,000. Capital: Dublin
. Although Ireland has been invaded and colonized by Celts, Norsemen, Normans, English, and Scots, ethnic distinctions are nonexistent. Languages: Irish, English (both official). Religion: Christianity (predominantly Roman Catholic; also Protestant). Currency: euro. Ireland's topography consists largely of broad lowlands drained by rivers that include the Shannon
; its coasts are fringed with mountains. About three-fifths of the population is urban; agriculture employs only a small percentage of the workforce. High technology, tourism, and other service industries are pivotal to the Irish economy, while mining, manufacturing, and construction also remain important. Ireland is a unitary multiparty republic with two legislative houses; its head of state is the president, and the head of government is the prime minister. Human settlement in Ireland began c.
6000 BC, and Celtic migration dates from c.
300 BC. St. Patrick
is credited with having Christianized the country in the 5th century. Norse domination began in 795 and ended in 1014, when the Norse were defeated by Brian Boru
. Gaelic Ireland's independence ended in 1175 when Roderic O'Connor, Ireland's high king, accepted English King Henry II as his overlord. Beginning in the 16th century, Irish Catholic landowners fled religious persecution by the English and were replaced by English and Scottish Protestant migrants. The United Kingdom of Great Britain and Ireland was established in 1801. The Irish Potato Famine of the 1840s led as many as two million people to emigrate, and about one million people died from starvation or from typhus or other famine-related diseases. The British government's grudging and ineffective relief measures built momentum for Irish Home Rule
. The Easter Rising
(1916) was followed by the Anglo-Irish War (1919–21), during which the Irish Republican Army used guerrilla tactics to force the British government to negotiate. The signing of the Anglo-Irish Treaty on Dec. 6, 1921, when ratified by the Dáil the following month, granted southern Ireland dominion status as the Irish Free State. Internecine struggle between supporters and opponents of the treaty culminated in the Irish Civil War (1922–23). In 1937 the Free State adopted the name Éire (Ireland) and became a sovereign independent country. It remained neutral during World War II. In 1948 the Dáil passed the Republic of Ireland Act, which took effect in April 1949, declaring Ireland a republic and removing it from the British Commonwealth of Nations. Britain recognized the new status of Ireland but declared that unity with the six counties of Northern Ireland could not occur without consent of the parliament of Northern Ireland. In 1973 Ireland joined the European Economic Community (later the European Community
); it is now a member of the European Union
. In the last decades of the 20th century, the issue of the political status of Northern Ireland prompted hostilities between Catholics and Protestants in the north and deep concern in the south, where there were a number of serious terrorist incidents. The Irish government played a pivotal role in negotiating and winning public support in 1998 for the Good Friday Agreement (Belfast Agreement), under which Ireland agreed to remove from its constitution its claim to the territory of the entire island (enacted in 1999). Ireland continued to play an important consultative role in Northern Ireland, such as helping to negotiate an agreement between the Democratic Union Party and Sinn Féin coalition government in 2010, under which policing and justice powers were to be devolved to Northern Ireland's government