In the United Kingdom, military conscription has existed for two periods in modern times. The first was from 1916 to 1920, and the second from 1939 to 1960. The last conscripted soldiers left the service in 1963. It was legally designated as "Military Service" from 1916 to 1920, and as "National Service" from 1939 to 1960. However, between 1939 and 1948, it was often referred to as "War Service" in documents relating to National Insurance and pension provision. Recruitment to the British Army during the First World War and Opposition to World War I Conscription during the First World War began when the British government passed the Military Service Act in January 1916. The act specified that single men aged 18 to 40 years old were liable to be called up for military service unless they were widowed with children, or were ministers of a religion. There was a system of tribunals to adjudicate upon claims for exemption upon the grounds of performing civilian work of national importance, domestic hardship, health, and conscientious objection. The law went through several changes before the war ended. Married men were exempt in the original Act, although this was changed in May 1916. The age limit was also eventually raised to 51 years old. Recognition of work of national importance also diminished. In the last year of the war there was support for the conscription of clergy, though this was not enacted. Conscription lasted until mid-1919. Due to the political situation in Ireland, conscription was never applied there; only in Great Britain (England, Scotland, and Wales). An attempt to do this caused huge backlash by the Irish public, defeating it, with Irish nationalism gaining significant support because of the crisis, eventually resulting in a successful war for independence. Conscription legislation lapsed in 1920. However, as a result of the deteriorating international situation and the rise of Nazi Germany, the Secretary of State for War, Leslie Hore-Belisha, persuaded the cabinet of Neville Chamberlain to introduce a limited form of conscription on 27 April 1939.