Co-founder with his older brother of a billion-dollar body-building empire, Ben Weider was responsible for launching Arnold Schwarzenegger’s career in the United States, writes Bill Gladstone.

His brother Joe, who with a sister survives him, first began lifting barbells as a scrawny teenager to respond to antisemitic taunts. Ben emulated him, building his own barbells from old car wheels and axles.

His publishing empire started with mimeographed sheets on a Gestetner copier, at a cost of $7. The brothers’ corporate empire eventually included magazines such as Muscle & Fitness, nutritional supplements, the rights to international bodybuilding competitions, and a line of home and gym exercise equipment.

After serving in the Second World War, they founded the International Brotherhood of Body Builders in 1946. In 1968 they brought Arnold Schwarzenegger, then a little-known Austrian bodybuilder, to the USA, where he became a movie star and then governor of California. Schwarzenegger acknowledged Weider’s role as a vital “stepping stone” since he had neither the knowledge nor the money to make the career-changing move on his own.

Weider’s great passion was Napoleon, whom he admired for emancipating European Jews from the ghetto. He collected rare Napoleonic artefacts, including a shirt made for Napoleon by a Jewish tailor who put a Magen David on to one of the buttons as a tribute.

He also owned several locks of Napoleon’s hair. From forensic tests on them, he concluded that Napoleon had been murdered by arsenic poisoning, a hypothesis he explored in a bestselling 1982 book, The Murder of Napoleon.

For this and other historical publications he was awarded the Légion d’Honneur by the French government and received Canadian honours, including the Order of Canada and l’Ordre du Quebec. He also gave generously to local Jewish charities.

His home was filled with, and indeed taken over by, his Napoleonic collection, of which he donated some 60 valuable pieces to the Montreal Museum of Fine Arts. The objects form the heart of a new permanent gallery on Napoleon that opened six days after his death.

He is survived by his wife, Huguette; and three sons, Louis, Eric and Mark.