Revenue stamps of the United Kingdom
When Ireland was partitioned into Northern Ireland and Southern Ireland in 1921, separate revenue stamps were issued for both entities. Southern Ireland stamps saw little use since that political entity was quickly superseded by the Provisional Government of Ireland and later the Irish Free State (both of which applied overprints on various British and Irish revenue stamps). However, Northern Ireland continued to use separate revenue stamps until the 1980s. Northern Irish revenues include Civil Service, Dog Licence, Excise and National Insurance stamps, among many others.
Partition of Ireland
The treaty "went through the motions of including Northern Ireland within the Irish Free State while offering it the provision to opt out". It was certain that Northern Ireland would exercise its opt out. The Prime Minister of Northern Ireland, Sir James Craig, speaking in the House of Commons of Northern Ireland in October 1922, said that "when the 6th of December is passed the month begins in which we will have to make the choice either to vote out or remain within the Free State." He said it was important that that choice be made as soon as possible after 6 December 1922 "in order that it may not go forth to the world that we had the slightest hesitation." On the following day, 7 December 1922, the Parliament resolved to make the following address to the King so as to opt out of the Irish Free State: