Irish Census: Northern Ireland documents among 'lost' records
Thousands of Irish census documents, many dating back to the early 19th Century, have been made available to the public online for the first time.
The vast majority of pre-1922 records were destroyed in the Irish Civil War by a fire at the Public Record Office.
But some of the documents that survived the fire, and others held elsewhere, have now been collated and put online.
They include partial census records from 1821 to 1851, a substantial amount from counties now in Northern Ireland.Pre-famine Ireland
Surviving documents from the 1821 census include household returns from large parts of County Fermanagh.
Many of the 1831 census records for County Londonderry have survived, and a substantial amount of 1851 census documents from County Antrim also remain intact.
Most of them are not the original documents, but are contemporaneous copies of census forms archived in offices in what later became Northern Ireland.
The surviving documents had previously been available to order from the Public Record Office of Northern Ireland (PRONI) but they have now been published online, to access free of charge, by the National Archives of Ireland.
It undertook the project in partnership with genealogical companies, FindMyPast and FamilySearch.
In total, the newly available documentation relates to more than 600,000 individuals on the island of Ireland.Documentation disasters
In addition to the Northern Ireland census records, they include documents from counties Cavan, Meath, Galway, Offaly and Dublin.
Many of the records are from the years leading up to the Irish famine, which is reckoned to have killed nearly one-eighth of the entire population.
The three partners involved in the project have described the online additions as a "substantial record of an important period in Irish history" and an "invaluable resource for anyone tracing Irish ancestry".
For people of Irish descent, tracing their family roots is notoriously difficult because of a series of documentation disasters.
Full government censuses for the whole island of Ireland began in 1821 and continued at ten-year intervals until 1911.
No census was taken in 1921, because of the Irish War of Independence.Bomb explosions
However, many of the records were completely destroyed prior to 1922, by order of the British government, on grounds of confidentiality.
The original census returns for 1861 and 1871 were destroyed shortly after they were taken.
Documents from the 1881 and 1891 censuses were pulped during the First World War.
The majority of the returns for the four censuses carried out between 1821 and 1851 were destroyed by a major fire at the Public Record Office of Ireland.
When the Irish Civil War began in June 1922, the government-owned building based at Dublin's Four Courts was among the first casualties.
Almost all of the records it held, some dating back to medieval times, were destroyed in bomb explosions that set fire to the office on 30 June of that year.100-year rule
As a result, the 1901 and 1911 Irish censuses are the only pre-partition censuses to survive in comprehensive form.
Census records are normally kept confidential and only released 100 years after the original surveys were completed.
However, because so many Irish census documents have been destroyed, the 100-year rule was suspended and the public were given early access to the 1901 and 1911 censuses.
They have been available to search online for free via the National Archives of Ireland for the last few years.
Catriona Crowe, the Head of Special Projects at the National Archives of Ireland, said the newly released documents also include "census search" forms, which recorded the personal details of Irish people who asked to search through the 1841 and 1851 censuses.
The searches were often undertaken by pensioners seeking to prove their own date of birth, in order to qualify for the Old Age Pension, which was introduced in 1909.
The search applicants had to give their name, address and parents' names, crucially including their mother's maiden name.'Tragic loss'
The documents were kept in an administrative section of the Public Records Office in Dublin and survived the 1922 fire.
Ms Crowe said they were a very valuable source of information for people who have very little information about their relatives from this period.
"The National Archives is delighted to be involved in this partnership, which allows us to make many of our important genealogical records available free online at a time of scarce government resources," she said.
"We look forward to rolling out many more records in the coming years," Ms Crowe added.
Cliona Weldon, general manager of Findmypast.ie, said: "Having such a priceless set of records available online to access for free is a huge benefit for everyone wanting to find their Irish roots, especially after the tragic loss of records in 1922."