Irish Boundary Commission - Wikipedia
▻https://en.wikipedia.org/wiki/Irish_Boundary_Commission
The Irish Boundary Commission (Irish: Coimisiún na Teorainne) met in 1924–25 to decide on the precise delineation of the border between the Irish Free State and Northern Ireland. The 1921 Anglo-Irish Treaty, which ended the Irish War of Independence, provided for such a commission if Northern Ireland chose to secede from the Irish Free State, an event that occurred as expected two days after the Free State’s inception on 6 December 1922.[1] The governments of the United Kingdom, of the Irish Free State and of Northern Ireland were to nominate one member each to the commission. When the Northern government refused to cooperate, the British government assigned a Belfast newspaper editor to represent Northern Irish interests.