The 1901 Census has been made available online today with over 4.5m individual records from 850,000 households.
Find out more about the census
Minister for Tourism, Culture and Sport Mary Hanafin launched the website containing the full records from the survey this morning.
This new site contains records from the 32 counties of Ireland, which were taken on census night in 1901.
It will now be available free of charge for everyone across the world to access and research.