Revenue stamps of Northern Ireland
Upon the partition of Ireland in 1921, separate revenue stamps began to be issued for both Northern Ireland and Southern Ireland. The latter were withdrawn soon afterwards upon the establishment of the Provisional Government, but the former continued to issue revenue stamps until the late 20th century. The need for separate issues for Northern Ireland came about since taxes raised there were meant to remain in the country. Most Northern Irish revenue stamps were British key types with appropriate inscriptions, but there were a number of different issues as well.
Dioceses of Ireland
The pre-Reformation Christian church in Ireland was first divided into dioceses at the Synod of Ráth Breasail in 1111, although the dioceses of Dublin and Waterford were founded earlier by Hiberno Norse rulers with bishops consecrated by the Archbishop of Canterbury in England. The boundaries were reconfigured at the Synod of Kells in 1152 into 37 dioceses. A few were later abolished, as when Glendalough merged Dublin in 1214–16.