Frere had stepped down as a director of GBL and GBL's Swiss-based shareholder Pargesa three years ago, though he remained one of the controlling shareholders of the group run since 2012 by his son-in-law, Ian Gallienne, who is co-CEO.

Frere attained international prominence in the early 1980s, helping divest some of nationalised French bank Paribas' foreign assets and setting up Pargesa with Canadian businessman Paul Desmarais, who died in 2013.

Both speaking native French with non-French accents, the pair forged a bond working together on Paribas.

"I guess the French asked themselves: ‘Who are those weirdos?’" Frere said in a rare newspaper interview in 2010.

With Pargesa’s backing, Frere took control of GBL in 1982. It survived the collapse in 1990 of its U.S. investment bank Drexel Burnham Lambert amid a scandal over its promotion of highly leveraged buyouts and "junk bonds".

His career started when he inherited his family business, trading in nails, and set out to acquire a string of steel businesses around his home city of Charleroi after World War Two. He left school to run the business aged 17.

"Albert Frere, honorary chairman and co-controlling shareholder of the company, passed away today," GBL said in a statement on its website on Monday.

"For more than three decades, under his leadership, GBL became one of the largest holdings in Europe. His professional and human qualities have deeply marked our group."

Through the group, Frere held significant stakes in some of Europe's biggest companies, including Adidas, Pernod Ricard, LafargeHolcim and Total.

Often Frere played a role as a consolidator, where he traded a large stake in a smaller company against a small stake in a larger company. This was the case in the sale of Belgian energy company PetroFina to Total, media group RTL to Bertelsmann, or in the giant cement merger between Lafarge and Holcim.

Together with Bernard Arnaud of France's LVMH luxury group, Frere, who was made a baron by the Belgian king, owned acclaimed French wine estate Chateau Cheval Blanc in Saint-Emilion near Bordeaux. But he himself never moved far from his birthplace near Charleroi, at the heart of Belgium's coal and steel belt.

(Reporting by Alastair Macdonald; Editing by Alissa de Carbonnel and Alexander Smith)

By Alastair Macdonald