Ireland By beastboss87 432 St.Patrick introduced Christianity to Ireland http://www.factmonster.com/country/ireland.html Dec 24, 917 Viking Invasion of Ireland Dec 24, 1171 In 1171, Henry II of England was acknowledged Lord of Ireland http://www.factmonster.com/country/ireland.html Dec 24, 1690 The Battle of the Boyne http://www.factmonster.com/country/ireland.html Dec 24, 1801 The act of the union http://www.factmonster.com/country/ireland.html Apr 24, 1916 Easter Rebellion in Dublin http://www.factmonster.com/country/ireland.html?pageno=2 Dec 6, 1922 The Irish Free State was established as a dominion http://www.factmonster.com/country/ireland.html?pageno=2 Dec 24, 1927 De Valera joined the government http://www.factmonster.com/country/ireland.html?pageno=2 May 22, 2015 Ireland became the first country to legalize same sex marriage last year http://www.factmonster.com/country/ireland.html?pageno=7