Until 1922 Ireland used British stamps and postal stationery, the first stamp for use in Ireland therefore being the 1840 Penny Black. Numerical cancellations of a design specific to Ireland were introduced in 1844, but otherwise the postal markings followed the normal pattern of the British provincial Post Offices.
The difficulty of controlling Ireland continued unabated during the Victorian and Edwardian eras. The demand for Home Rule increased during this period and led to open revolution in 1916. Nevertheless, the postal service was maintained and British stamps continued to be used. The normal British postmark types were used and British pillar boxes were erected in Irish towns.
A national parliament was established at the end of 1918 and it affirmed the independent status of Ireland in January 1919. No adhesives were issued at this period, though some propaganda labels were produced. The Irish Free State was formed following elections in 1921. In 1925 the boundary between Ireland and Ulster (Northern Ireland) was settled. A supply of British stamps printed by Harrisons (low values) or Bradbury Wilkinson (2s6d, 5s & 10s) were overprinted in Ireland by Dollard Limited or Alex Thom & Co. A small number were also overprinted in England by Harrisons. The first unoverprinted stamp issue of Ireland began to appear on 6 December 1922, a definitive series depicting the “Sword of Light”, a map of Ireland, the Arms of Ireland and a Celtic Cross. The first Commemorative issue was the 1929 Catholic Emancipation set featuring Daniel O’Connell.
We recommend the stamp listings in the Stanley Gibbons “Ireland” catalogue, also the excellent “Hibernian Handbook and Catalogue of The Postage Stamps of Ireland” which includes the Political and Propaganda stamps, Essays and Trials, Varieties and Errors and excellent information on the 1922 overprints amongst much else.