In 1911, the whole of the island of Ireland was still part of the United Kingdom and therefore the census was taken on the same day as that for England, Wales and Scotland, the 2nd April 1911.
The information asked for was similar to the rest of the UK, in the case of Ireland being name, age, sex, relationship to head of the household, religion, occupation, marital status, county or country of birth, the ability to read or write, the ability to speak the Irish language, and whether deaf, dumb, blind, idiot, imbecile or lunatic. In addition married women were required to state the number of years they had been married, the number of children born alive in that marriage and the number still living.
The question on religion was very specific with instructions that "Members of Protestant Denominations are requested not to describe themselves by the vague term 'Protestant' but to enter the name of the Particular Church, Denomination, or Body to which they belong".
The 1911 Irish census is available now for all 32 counties of the island of Ireland, for free, at the National Archives of Ireland website. The full 1901 Irish census is also available on the same site.
The 32 counties are Antrim, Armagh, Carlow, Cavan, Clare, Cork, Donegal, Down, Dublin, Fermanagh, Galway, Kerry, Kildare, Kilkenny, King's County (Offaly), Leitrim, Limerick, Londonderry (Derry), Longford, Louth, Mayo, Meath, Monaghan, Queen's County (Laois), Roscommon, Sligo, Tipperary, Tyrone, Waterford, Westmeath, Wexford and Wicklow.
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