Mr Fitzpatrick, who also had significant property interests, played an active role in the Belfast-based paper for more than 50 years, assuming control of the title in the early 1980s.
His tenure at the helm of Northern Ireland’s only nationalist daily coincided with some of the worst years of the Troubles.
A man of deep Catholic faith, Mr Fitzpatrick’s staunch repudiation of the region’s violent conflict often put him at odds with the republican movement, most notably in 1982 when he banned IRA references in death notices in the paper.
The father of eight, whose wife Alice died in 2013, was a regular fixture in the Irish News offices well into his 90s, retaining a keen interest in the family-run institution.
The paper’s editor Noel Doran paid tribute to his legacy.
“Jim Fitzpatrick was a giant of the newspaper industry as well as a key figure in the search for peace and reconciliation in Ireland who also had significant roles in law, business and the arts.
“Although he maintained a low profile, he was a noted philanthropist who probably had the strongest personal faith of anyone I have ever met.
“He was completely dedicated to his family and to his staff at all levels in The Irish News, and serving as his editor for the last 24 years has been the greatest privilege of my career.”
Taoiseach Micheal Martin expressed his “deep sadness and sympathy” at the passing of Mr Fitzpatrick.
“I had the great privilege of knowing and interacting with Jim over many years. He was, in every respect, a true gentleman.
“In his decades-long stewardship of The Irish News, he was a profoundly important advocate for an end to violence in the North. His role in the earliest days of the embryonic peace process is not widely known, but it was crucial.
“In his support for and leadership of the Chamber of Commerce in Belfast, he brought together people from all backgrounds in common constructive cause and was an example of true civic leadership.
“In his quiet and ceaseless philanthropy over a lifetime, his generosity has left its stamp all across Belfast and further afield.
“Jim had a deep and true faith, which he carried with kindness and humility, and which sustained him following the sad death of his beloved wife Alice in 2013.
“Jim’s eight children and wider family circle will feel his loss acutely, but I hope that they can also take comfort and some pride in the knowledge that their father made a genuinely positive contribution to Belfast and to Ireland over the course of his life.
“To Anne, Brid, Bernard, Eileen, Dominic, Clare, Jim Jnr and Andrew, to the wider family circle, to his colleagues in The Irish News, and to his many friends I offer my heartfelt condolences.
“Ar Dheis De go raibh a anam dilis.”
SDLP leader Colum Eastwood said Mr Fitzpatrick “was one of the giants of news in Ireland”.
“During the most difficult periods of our recent past, Jim was fearlessly devoted to telling the stories of ordinary people who had suffered the most extraordinary loss and he did it without favour, even when it meant putting himself at odds with the men of violence.
“He was a man committed to the truth, to fairness and to peace on our island.
“Jim’s passing feels like the end of an era for many of us, but it will be felt most acutely by his colleagues to whom he was unimpeachably loyal and of course his family, who he lived every day for and of whom he was unfailingly proud.
“My thoughts and the thoughts of the entire SDLP family are with Jim’s children Anne, Brid, Bernard, Eileen, Dominic, Clare, Jim and Andrew at this incredibly difficult time.
“I hope they are comforted by the knowledge that their dad lived an extraordinary life and that his dedication to peace saved many others.”
Dominic Fitzpatrick, managing director of The Irish News, paid tribute to his father on Saturday.
“As a family we were blessed with incredible parents,” he said.
“Dad was an inspiration to so many people.
“His desire to be involved in The Irish News was driven by a belief that society needed a newspaper that could stand for truth and justice, particularly at such a turbulent time in history.
“Under his direction the paper has been transformed into the success it is today.
“He spent much of his life helping in the search for peace in Ireland, working quietly but effectively in the background.
“He was involved in community work, continually trying to bring people together and improve society.
“Dad really cared about people.
“He loved his work and was still coming to the office until a few weeks ago.
“He had a morning prayer which he said every day and it pretty much summed up his attitude to life.
“He saw every day in life as an opportunity to be seized, a gift from God not to be wasted.
“A day where he would be thoughtful, generous and helpful to others and lived without regret.”
Born in 1929, Mr Fitzpatrick’s early childhood was spent in Belfast before his family moved to rural Co Down during World War Two.
He was educated in a boarding school in Limerick and studied law at university in Galway.
Mr Fitzpatrick began his working life as a solicitor, practising in his father James’s firm in Belfast.
James snr was a director at the Irish News, which was then owned by the McSparran family from Co Antrim.
He inherited his father’s passion for journalism and started becoming more involved in the newspaper trade himself during the turbulent years of the late 1960s.
In 1969, he was also appointed an Irish News director, the same year as the Troubles began.
Soon after he took a journalism course and began to write for the paper.
The 1980s would see him become managing editor and then chairman of the title.
While the ownership arrangements of other local dailies changed several times in the decades since, the Fitzpatrick family’s stewardship of the Irish News remained a constant, as it solidified its reputation as one of the leading outlets on the island of Ireland.