Irish constitutional referendums, 1998

Two referendums were held together in the Republic of Ireland on 22 May 1998, each on a proposed amendment of the Irish constitution. Both measures were approved. A referendum in Northern Ireland was also held on the same day.

The Eighteenth Amendment introduced two new articles into the constitution which allowed the government to ratify the Amsterdam Treaty.

The Nineteenth Amendment to the constitution allowed the government to ratify the Good Friday Agreement done at Belfast on 10 April 1998, which included changing articles 2 and 3 of the Irish constitution which effectively claimed Irish sovereignty over Northern Ireland. The agreement was also endorsed in the simultaneous referendum in Northern Ireland. Articles 2 and 3 were subsequently changed in December 1999.

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