The date of the game is at the same time changes were taking place within the whole of Irish football. Some details below.
Summary
1880 – IFA founded in Belfast, representing all of Ireland ("Ireland")
1921 – FAI founded in Dublin, representing Southern Ireland ("Irish Free State")
1936 – FAI begins also selecting Northern players ("Ireland"/"Éire")
1946 – FAI stops selecting Northern players ("Republic of Ireland" as of 1954)[3]
1950 – IFA stops selecting Southern players ("Northern Ireland" as of 1954)[3]