Joint Website of the The National Archives, Ireland and The Public Record Office of Northern Ireland
Many records were created before Ireland was partitioned and after the Anglo-Irish Treaty of 1921, some, such as the Tithe Applotment Books and National School records were split on a county basis. Some records, however, are not split as precisely as this implies. Parish boundaries, for example, straddle the border and so divisions have been made on what seems to the Archives a reasonable basis. With privately deposited records, donors are free to place their records in whichever repository they choose. The joint website is to help researchers establish in which Record Office the archives are held.