A mystery revolving around President Barack Obama’s Irish roots was solved when a tomb containing the remains of Obama’s Irish ancestor was discovered in the Irish medieval city of Kilkenny.

After a painstaking search, film maker Gabriel Murray, who is in the process of making a documentary on Obama's Irish roots, finally found “Obama’s Lost Tomb” inside the 13th century St. Canice’s Cathedral.

Murray, along with Cathedral assistant Frances Moore, used a centuries-old map to identify a hidden vault under the floor of St. Canice’s. They deciphered the Latin on the hundreds of tombs inside the vault, when they came across Bishop John Kearney’s resting place, number 19 on the map, just 20 yards from the main entrance.

"I have to admit it was very exciting and it was great to finally prove conclusively that Barack Obama's sixth generation grand uncle was the Bishop of Ossory and a former provost of Trinity College who died in Kilkenny city at the Bishop's Palace in 1813. It is now the headquarters of the Heritage Council," Murray told the Kilkenny People.

"The Palace is the site of the only building in existence that is directly linked to Bishop John Kearney and so to Obama," the historian added.

Obama’s links to Moneygall, County Offaly were established during his presidential run. His great-great-great grandfather on his mother's side, Fulmouth Kearney, was born and grew up there before emigrating to the U.S. in 1850.

But Murray uncovered the U.S. president’s links to Kilkenny when he found documentation in the ancient archive department at Trinity College, Dublin, that stated that Bishop Kearney was buried in a tomb in St. Canice’s Cathedral.

"To be honest, I still can't believe that I managed to find it," Murray said.

The historian’s documentary, “Obama’s Irish Roots,” follows the Kearney family's 5,000-mile route from Kilkenny to Kansas in 1847 during the Great Famine. The film features interviews with Obama’s Irish relatives in both Ireland and America, and features reenactments of the life of Obama's great-grandfather and great-grandmother.

The direct Irish link to Obama is just one of the many secrets St. Canice’s is thought to hold.

The building  has played a central role in the life of Kilkenny, and worship has taken place at the site for over 800 years.