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 The latter were withdrawn soon afterwards upon the establishment of the Provisional Government, but the former continued to issue revenue stamps until the late 20th century.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.
Northern Ireland
The Troubles were brought to an uneasy end by a peace process which included the declaration of ceasefires by most paramilitary organisations and the complete decommissioning of their weapons, the reform of the police, and the corresponding withdrawal of army troops from the streets and from sensitive border areas such as South Armagh and Fermanagh, as agreed by the signatories to the Belfast Agreement (commonly known as the "Good Friday Agreement"). This reiterated the long-held British position, which had never before been fully acknowledged by successive Irish governments, that Northern Ireland will remain within the United Kingdom until a majority of voters in Northern Ireland decides otherwise. The Constitution of Ireland was amended in 1999 to remove a claim of the "Irish nation" to sovereignty over the entire island (in Article 2).
The new Articles 2 and 3, added to the Constitution to replace the earlier articles, implicitly acknowledge that the status of Northern Ireland, and its relationships within the rest of the United Kingdom and with the Republic of Ireland, would only be changed with the agreement of a majority of voters in each jurisdiction. This aspect was also central to the Belfast Agreement which was signed in 1998 and ratified by referendums held simultaneously in both Northern Ireland and the Republic. At the same time, the British Government recognised for the first time, as part of the prospective, the so-called "Irish dimension": the principle that the people of the island of Ireland as a whole have the right, without any outside interference, to solve the issues between North and South by mutual consent. The latter statement was key to winning support for the agreement from nationalists. It established a devolved power-sharing government within Northern Ireland, which must consist of both unionist and nationalist parties. These institutions were suspended by the British Government in 2002 after Police Service of Northern Ireland (PSNI) allegations of spying by people working for Sinn Féin at the Assembly (Stormontgate). The resulting case against the accused Sinn Féin member collapsed.