Captain Sir John Leslie Bt, a member of the family that owns the Castle Leslie estate in Co Monaghan, has died at the age of 99.
He was one of Ireland's last surviving World War II veterans, and was a cousin of Winston Churchill.
Captain Leslie passed away in his sleep this morning, surrounded by his family.
His family described him as an active Knight of Malta, art connoisseur, water colourist, ecologist, disco-dancer and restorer of historic buildings.
Last November Sir Jack was awarded France's highest award for his role in the country's liberation.
He toasted the Legion d'Honneur with a glass of champagne in the French embassy in Dublin and dedicated it to "all soldiers from the island of Ireland who fought and died between the two great wars".
Ambassador of France to Ireland Jean-Pierre Thébault paid tribute this afternoon, saying: "With Sir John Leslie, France loses a friend and mourns a hero. Like thousands of other Irishmen and Irishwomen, he voluntarily enlisted and put his life, his future, at risk in the darkest hours of World War II, to fight for freedom and all the core values of our free societies. Their legacy will always inspire us."
Sir Jack became an international news sensation in 2002 as his castle hosted Sir Paul McCartney's wedding to Heather Mills.
With the global media gathered at the gates of the estate near Glaslough he announced the superstar's nuptials were taking place behind the gates but that it was "a secret".
Known for his love of house music in his later years, he celebrated his 85th birthday in 2001 by travelling to Ibiza to party at Privilege, then the world's biggest nightclub.
The family said this taste in music was "perhaps one of the most endearing of Uncle Jack's hobbies".
"Each week he would visit the local night club to dance to the "boom boom" music. He quickly gained respect in the clubbing community to the extent there is a nightclub named after him in Clones, Co Monaghan," they said.
Leslie spent five years as prisoner of war
His family said he was blessed with an astonishing memory for people, places and events and he was interviewed many times and appeared in a number of documentaries.
Sir Jack enlisted in the Second Battalion of the Irish Guards in August 1937, at the age of 21.
Three years later he was part of the British Expeditionary Force, landing in France in May 1940.
Commanding a section that battled for two hours to defend Boulogne-sur-Mer against advancing Germans, he was captured and spent the next five years as a prisoner of war.
It was believed for a time that he had been killed in action.
During his captivity, he risked his life to spirit out a postcard to his cousin Mr Churchill pleading for a POW exchange to allow some of his comrades in the camp who had taken ill to be freed.
The letter hangs in the Imperial War Museum in London.
In 2009 he published his memoires - Never A Dull Moment.
He will be buried in a private burial enclosure next to the estate church of St Salvator where he has already prepared his tombstone.
Sir Jack turned 99 last December.
After being released from German captivity in 1945, he travelled the world before settling for some time in Rome, where he bought a 1,500-year-old monastery.
He became the 4th Baronet of Glaslough and Pettigo at Castle Leslie when his father died in 1971.