A systematic
government census of the Irish population was taken every 10 years
between 1821 and 1911. The 1901 and 1911 censuses are the only
surviving full censuses of Ireland open to the public.
Both censuses cover the island of Ireland and were released to public
inspection in 1961 and made available online in 2009. No census was
taken in 1921 due to the Irish War of Independence.
The first census of the Irish Free State was taken in 1926. The 1926
census is being released to researchers after 100 years in April 2026.