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 Southern Ireland stamps saw little use since that political entity was quickly superseded by the Provisional Government of Ireland and later the Irish Free State (both of which applied overprints on various British and Irish revenue stamps).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.
Irish War of Independence
In May 1921, Ireland was partitioned under British law by the Government of Ireland Act, which created Northern Ireland. Both sides agreed to a ceasefire (or 'truce') on 11 July 1921. The post-ceasefire talks led to the signing of the Anglo-Irish Treaty on 6 December 1921. This ended British rule in most of Ireland and, after a ten-month transitional period overseen by a provisional government, the Irish Free State was created as a self-governing Dominion on 6 December 1922. Northern Ireland remained within the United Kingdom. After the ceasefire, violence in Belfast and fighting in border areas of Northern Ireland continued, and the IRA launched a failed Northern offensive in May 1922. In June 1922, disagreement among republicans over the Anglo-Irish Treaty led to the ten-month Irish Civil War. The Irish Free State awarded 62,868 medals for service during the War of Independence, of which 15,224 were issued to IRA fighters of the flying columns.