The Troubles refers to the 30-year period of violence in Northern Ireland between Nationalist Catholics who wanted to unite with Ireland and Unionist Protestants who wanted to remain part of the UK. This violence was carried out by paramilitary groups like the IRA and resulted in over 3,000 deaths and tens of thousands injured. Key events included Bloody Sunday, internment without trial, hunger strikes, and the Omagh bombing. The Good Friday Agreement in 1998 largely ended the violence by establishing power sharing and recognizing both communities.