"There was a redistribution of constituencies, following the Anglo-Irish Treaty and the establishment of the Irish Free State. Twenty-six of the thirty-two Irish counties ceased to be represented in the United Kingdom Parliament. The remaining six counties formed Northern Ireland. All seats were single member, except for Antrim, Down and Fermanagh & Tyrone. Those three seats elected two members each. Some seats included parts of more than one county. The predominant county when the constituency is created is named in those cases."