For the first time, people will be able to search for their ancestors by first or family name. Anyone whose ancestor was in Dublin in 1911— whether as a tenant, a lodger, a servant, a policeman, a soldier, a member of a religious congregation or, more sadly, in a hospital or a workhouse — now has a chance to find them.

The digitisation of the equivalent records for England, Wales and Scotland has proved hugely popular with users, as has the digitisation of Canadian and US census records, but the Irish project differs from other census websites in some important respects. Crucially — and something to be publicised and applauded at every available opportunity — the material is available free of charge, whereas the British, Scottish and US census records are only available at a charge to the user.

One reason this decision was made is because of the overwhelming importance of any Irish records that survived the catastrophic fire in the Public Records Office in the Four Courts at the beginning of the Civil War in 1922.

This was an occurrence accurately described during the week by Catriona Crowe, the archivist who has overseen the census project, as “an act of unparalleled cultural vandalism”.

During this calamitous inferno, all the census material for the 19th century was destroyed, along with countless other records from the early 14th century to the late 18th century.

Ireland is also lucky to have the original household forms from the 1911 census that were distributed by 4,000 census enumerators in the lead-up to census day on April 4, 1911; most other countries only have books containing transcribed information. Our census forms were filled out by our ancestors in their own handwriting and signed by the head of the household, which gives them a magic unmatched by the records of other countries, and the original forms can now be downloaded.

To accompany the website and index of names, the National Archives has also provided detailed historical analysis and illustrative material to bring alive the Dublin of 1911.

The researcher can read about transport and look at a tram timetable for 1911 (there were 330 trams in Dublin then, operating on lines that ran for 60 miles around the city, part of a public transport system that was one of the most impressive of any city in the world then).

Social life is also covered, including photographs of the royal visit in 1911, as is education, Dublin’s literary life (Oliver St John Gogarty’s census return indicates that he momentarily forgot he was married), the trade union movement, government and politics, law and order, and poverty, health and welfare.

There are also many reminders that Dublin was a city of great contrasts, seen in the vast number of servants required to keep the vice-regal lodge in Phoenix Park ticking over for the benefit of the Lord Lieutenant, Lord Aberdeen, and his wife, Lady Aberdeen, the women’s rights activist and founder of the Women’s National Health Association.

At the exclusive Kildare Street Club, there were six visitors on census night, including a landowner, a land agent, a retired colonel, the official starter at Irish race meetings and Lord Fermoy. A staff of 32 attended to their comfort.

The German waiters from the Shelbourne Hotel lived nearby on Kildare Street, while WB Yeats and Lady Gregory were staying around the corner in Nolan’s Hotel on South Frederick Street.

There is no return for a number of well-known Irish feminists, including Hanna Sheehy Skeffington, as she and a number of other suffragettes refused to co-operate with the census in protest at the lack of the vote and remained defiant in the face of the threat of legal action.

But perhaps the greatest value of the census records is the detailed picture you can build of ordinary people living their lives and, unfortunately, experiencing the death and deprivation of loved ones.

The 1911 census asked a new question of women — how many children had been born to them, and how many remained alive?

Their answers bring abstract statistics about child mortality right down to the household level. Particularly in the inner city tenements, you can see terrible attrition, with losses of more than 50% of children to many families. Ten families lived at 24 Gloucester Street in 1911, for example, most families in one room. At that address, 47-year-old Annie Doran had given birth to eight children; only three survived.

Her neighbour in the same house, 44-year-old Katherine Cavanagh, had lost four of 10 children, and another neighbour in the house, Catherine Taylor, had lost two of five. There was no economic growth in Dublin in 1911 but the coffin makers were busy and rich. Overall, the death rate in Dublin in 1911 per thousand people was 22.3. In London it was 15.6.

The Dorans and the Taylors, each family numbering five, lived in one room apiece, while the Cavanaghs, with six, had two rooms.

IN DUBLIN that year, 26,000 families lived in one-room dwellings, making it the most overcrowded city in Europe. The decay of Dublin was epitomised by Henrietta Street on the northside of the city, where an astonishing 835 people lived in just 15 houses. The street had once been salubrious and home to a generation of lawyers, but by 1911 it was overflowing with poverty.

At 10 Henrietta Street, the Sisters of Charity ran a laundry with more than 50 single women living in the house. There were members of 19 different families living in No 7.

Among the 104 people who shared the house were charwomen, domestic servants, labourers, porters, messengers, painters, carpenters, a postman, a tailor and a whole class of schoolchildren. Out the back there was a stable and a piggery.

This historical context aspect of the website will feed the hunger for a deeper knowledge of the circumstances in which people’s ancestors lived.

The website, and its future expansion, is a huge step forward in making some of our most important documentary heritage accessible in the most modern and easily usable way.

The future of the internet depends on high-quality content. What you will find on this site (www.census.nationalarchives.ie) is unique, valuable, educational, entertaining and moving.