Ireland was part of the United Kingdom of Great Britain and Ireland when the world's first postage stamps were issued in 1840. These stamps, and all subsequent British issues, were used in Ireland until the new Irish Government assumed power in 1922. Beginning in February 1922, existing British stamps were overprinted with Irish text to provide some definitives until separate Irish issues became available.

Following the overprints, a regular series of definitive stamps was produced, using domestic designs.