The United Kingdom of Great Britain and Ireland was established on 1 January 1801 under the terms of the Acts of Union 1800, by which the nominally separate kingdoms of Great Britain and Ireland were united. In 1922, twenty-six of thirty-two counties of Ireland seceded to form the Irish Free State (later becoming the Republic of Ireland) and, to reflect the change in the United Kingdom's boundaries, the Royal and Parliamentary Titles Act 1927 formally amended the name of the UK Parliament to the "Parliament of the United Kingdom of Great Britain and Northern Ireland".