 The pro @-@ independence republican party , <unk> <unk> , received overwhelming endorsement in the general election of 1918 , and in 1919 proclaimed an Irish Republic , setting up its own parliament ( Dáil <unk> ) and government . Simultaneously the Volunteers , which became known as the Irish Republican Army ( IRA ) , launched a three @-@ year guerrilla war , which ended in a truce in July 1921 ( although violence continued until June 1922 , mostly in Northern Ireland ) . 
