BRITAIN'S Chancellor George Osborne, US President Barack Obama and author CS Lewis are among a host of public figures whose Irish ancestry is revealed by an online database.
The predecessors of Walt Disney, Oscar Wilde and John F Kennedy also feature in the updated online collection of 19th century historical Irish records, which has been published ahead of St Patrick's Day.
The records cover the critical period around the Famine and are especially valuable as a substitute for 19th century censuses, most of which were destroyed during the civil war.
George Osborne is heir to the Osborne baronetcy of Ballentaylor. His great great great grandfather, Sir Henry Osborne, can be found in the Tithe Applotment Books, living in Co Tipperary in 1824.
Also contained among the Tithes, featuring more than 600,000 Irish land tax records, is Barack Obama's great great great great grandfather who was living in Ballygurleen, Tipperary in 1829.
More than a quarter of US presidents have claimed Irish roots, including JFK whose great great grandfather Patrick Kennedy lived in Wexford. His name is found in Griffith's Valuation of Ireland, 1848-1864, which features more than 2.5 million names and addresses in land tax records.
Griffith's also shows William Wilde, father of Oscar Wilde, living at Westland Row, Dublin, where the author was born in 1854.
The website's content director Dan Jones said: "The new collections will be hugely relevant to anyone with Irish ancestry as they may hold the earliest or final record of their ancestors' existence.
"The Famine caused a huge spike in international emigration from Ireland -- meaning today, people from every corner of the globe may find they have Irish ancestry."
In an ICM poll of 2,000 British adults carried out for St Patrick's Day, one in five people said they had Irish ancestry. But the survey found only 15pc of people were able to name the Irish capital city.
The Irish Collection on Ancestry now contains more than 35 million historical records, as well as 20,000 photographs taken between 1870 and 1910, and almost 2,000 historic maps. A free 14-day trial is available at ancestry.co.uk/Irishrecords.