Through the early 20th century, Home Rule became the focus of political debate. It drew opposition from the island's Protestants, who vowed to resist the movement with violence.
The start of World War I prevented the enactment of Home Rule, which was passed by the House of Commons for the second time in 1914. Still the movement for self-rule continued.
In 1916, Irish nationalists stormed the General Post Office and other key buildings in Dublin during Easter week, proclaiming the formation of an Irish republic. The uprising, now known as the Easter Rising, failed and most of the leaders were eventually executed. However, the action created a large amount of sympathy for the recently found Sinn Fein political party (Irish for "Ourselves"; advocated Irish independence) and its leader Eamon de Valera, who barely escaped execution for his role in the Rising. The popular support was visible in the 1918 general election: Sinn Fein won 73 seats to the 31 for the Unionist and Independent Unionist parties, which both supported governance from London.
The next year, Sinn Fein boycotted Westminster, declaring the formation of its own "Dail Eireann" or Irish Parliament in Dublin with de Valera as its President. Violence escalated as the Irish Republican Army (IRA), led by Michael Collins, and fought Britain in a bloody war for independence- one that ended with the partitioning of the northern and southern parts of the island by the Government of Ireland Act in 1920.
The partitioning would have a lasting effect on the island as the act provided for separate parliaments: one in Belfast, serving six counties in the north and the other in Dublin for the remaining 26 counties. The area of Northern Ireland proved to be a place were the majority remained in favor of a union with Britain. In December 1921, Sinn Fein and British officials signed the Anglo-Irish Treaty, it created an Irish Free State over the southern 26 counties, and a northern state of six counties allied with Britain.
