Prime Minister David Lloyd George failed to introduce Home Rule in 1918 and in the December 1918 General Election Sinn Féin won a majority of Irish seats. Its MPs refused to take their seats at Westminster, instead choosing to sit in the First Dáil parliament in Dublin. A declaration of independence was ratified by Dáil Éireann, the self-declared Republic's parliament in January 1919. An Anglo-Irish War was fought between Crown forces and the Irish Republican Army between January 1919 and June 1921. The war ended with the Anglo-Irish Treaty of December 1921 that established the Irish Free State. Six northern, predominantly Protestant counties became Northern Ireland and have remained part of the United Kingdom ever since, despite demands of the Catholic minority to unite with the Republic of Ireland. Britain officially adopted the name "United Kingdom of Great Britain and Northern Ireland" by the Royal and Parliamentary Titles Act 1927. The failed international law system, after World War Two was replaced with the United Nations where the UK held a permanent seat on the UN Security Council. However the British Empire began to crumble as India, Israel and nations across Africa fought for democracy, human rights, and independence. To prevent any recurrence of the Holocaust and war, the Council of Europe was established to draft the European Convention on Human Rights in 1950. Further it was seen that the only way to prevent conflict was through economic integration. The European Economic Community, which became the European Union in 1992, was supported by Winston Churchill with the UK to be "at the centre", although it did not enter until the European Communities Act 1972. Under Margaret Thatcher, significant cuts were made to public services, labour rights, and the powers of local government, including abolishing the Greater London Council. However some powers were restored with extensive devolution of power in the Scotland Act 1998, Northern Ireland Act 1998, Greater London Authority Act 1999 and the Government of Wales Act 2006. After many years of armed conflict in Northern Ireland, the Good Friday Agreement of 1998 brought peace. The Life Peerages Act 1958 had allowed the creation of life peers which gave the Prime Minister the ability to change the composition of the House of Lords. The House of Lords Act 1999 reduced but did not fully eliminate hereditary peers. An important recent change in constitutional law came about with the Fixed-term Parliaments Act 2011, which significantly altered the way in which parliament can be dissolved. Then, following a referendum on EU membership in 2016 that resulted in 52.89 per cent of people favouring to leave, the United Kingdom ceased to be a member of the European Union on 31 January 2020.