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 The latter were withdrawn soon afterwards upon the establishment of the Provisional Government, but the former continued to issue revenue stamps until the late 20th century.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.
Partition of Ireland
Since partition, a key aspiration of Irish nationalists has been to bring about a reunited Ireland, with the whole island forming one independent state. This goal conflicts with that of the unionists in Northern Ireland, who want the region to remain part of the United Kingdom. The Irish and British governments agreed, under the 1998 Belfast Agreement, that the status of Northern Ireland will not change without the consent of a majority of its population. In its white paper on Brexit, the United Kingdom government reiterated its commitment to the Belfast Agreement. With regard to Northern Ireland's status, it said that the UK Government's "clearly-stated preference is to retain Northern Ireland’s current constitutional position: as part of the UK, but with strong links to Ireland".