continuing union with Britain. Unionists and Home Rule advocates were the main political factions in late 19th- and early 20th-century Ireland. 1912–1922 By the second decade of the 20th century, Home Rule, or limited Irish self-government, was on the brink of being conceded due to the agitation of the Irish Parliamentary Party. In response to the campaign for Home Rule which started in the 1870s, unionists, mostly Protestant and largely concentrated in Ulster, had resisted both self-government and independence for Ireland, fearing for their future in an overwhelmingly Catholic country dominated by the Roman Catholic Church. In 1912, unionists led by Edward Carson signed the Ulster Covenant and pledged to resist Home Rule by force if necessary. To this end, they formed the paramilitary Ulster Volunteer Force (UVF). In response, nationalists led by Eoin MacNeill formed the Irish Volunteers in 1913, whose goal was to oppose the UVF and ensure enactment of the Third Home Rule Bill in the event of British or unionist recalcitrance. The outbreak of the First World War in 1914, and Ireland's involvement in the war, temporarily averted possible civil war in Ireland and delayed the resolution of the question of Irish independence. Home Rule, although passed in the British Parliament with Royal Assent, was suspended for the duration of the war. The Irish Volunteers split, with a majority, known as the National Volunteers, supporting the war effort, and some of them joining Irish regiments of the New British Army. Many of those who stayed were radical nationalists, among them Irish Republican Brotherhood infiltrators. From these ranks came those who launched the Easter Rising in Dublin in 1916, led by Patrick Pearse and James Connolly. Two-and-a-half years after the executions of sixteen of the Rising's leaders, the separatist Sinn Féin party won the December 1918 general election in Ireland with 47% of the vote and a majority of seats, and set up the 1919 First Dáil (Irish Parliament) in Dublin. Their victory was aided by the threat of conscription for First World War service. The Irish War for Independence followed, leading to eventual independence in 1922 for the Irish Free State, which comprised 26 of the 32 Irish counties. In Ulster, particularly in the six counties which became Northern Ireland, Sinn Féin fared relatively poorly in the 1918 election, and unionists won a majority. The Government of Ireland Act 1920 partitioned the island of Ireland into