The fight for connection with Ireland was led by the Irish Republican Army (IRA).

An excerpt from the article 39 facts about Ireland

At the end of the 1960s, a bloody conflict broke out in Northern Ireland between republicans seeking to unite the island and unionists. It was only in 1998 that the Good Friday Agreement was concluded, for which two of its co-authors - John Hume and David Trimble - received the Nobel Peace Prize.