during the period when what is now the Republic of Ireland
formed a part of it.
The United Kingdom of Great Britain and Ireland came into being on 1 January 1801 under the terms of the Acts of Union 1800, by which the formerly separate kingdoms of Great Britain
were united. (The Kingdom of Great Britain had itself been formed in 1707 by the union of the formerly separate kingdoms of England
By the 1921 Anglo-Irish Treaty
the greater part of Ireland became independent on 6 December 1922 as the Irish Free State
1800 The Act of Union 1800 is passed in which merges the Kingdom of Great Britain and the Kingdom of Ireland into the United Kingdom of Great Britain and Ireland.
1801 The legislative union of Kingdom of Great Britain and Kingdom of Ireland is completed to form the United Kingdom of Great Britain and Ireland.
1803 The Convention of Artlenburg leads to the French occupation of Hanover (which had been ruled by the British king).
1812 War of 1812: American frigate ''USS Constitution'' defeats the British frigate ''HMS Guerriere'' off the coast of Nova Scotia, Canada earning her nickname "Old Ironsides".
1813 War of 1812: three weeks of British raids on Fort Schlosser, Black Rock and Plattsburgh, New York begin.
1814 Washington, D.C. is burned and White House is destroyed by British forces during the War of 1812.
1815 Signing of the Kandyan Convention treaty by British invaders and the King of Sri Lanka.
1820 Cato Street Conspiracy: A plot to murder all the British cabinet ministers is exposed.
1830 Charles Grey, (2nd Earl Grey), became Prime Minister of the United Kingdom.
1831 William IV and Adelaide of Saxe-Meiningen are crowned King and Queen of the United Kingdom of Great Britain and Ireland.