Special acts of worship ordered by the Irish government and the Church of Ireland were observed in only a minority of Irish places of worship, as the majority of the population was Roman catholic or, in parts of northern Ireland, protestant dissenters from the established church.
Little evidence survives for special worship before the 1620s. From the 1660s onwards, the government in Dublin and the Church of Ireland’s archbishops largely followed the occasions observed in England and Wales, waiting on orders or information from London. Given slow communication links, there was often delay, with Irish occasions ordered and observed later than those in England.
On the union of Ireland with England and Wales in 1801, the Church of Ireland became part of the United Church of England and Ireland. The Irish provinces of this church were disestablished in 1871. In consequence, further special acts of worship in Ireland are not included in the National Prayers volumes and are noticed there and in the following lists only when they were part of general observances for the United Kingdom of Britain and Ireland (to 1921), and later Northern Ireland.