For a man facing daily attacks for his activism and liberal vision of the world, George Soros was in a curiously buoyant mood on a sunswept afternoon in Marrakesh. He had just visited South Africa, home to his first philanthropic foray in the late 1970s, when he funded black students under apartheid. This time he learnt that Soros-backed investigative media and civil society groups had helped thwart an allegedly corrupt nuclear power plant contract with Russia.

“It was a tremendous boost to reinforce my belief that we are doing something right,” says Mr Soros. “We haven’t stopped having a beneficial influence.”

Influence has come at a painfully high cost for the 88-year-old father of the hedge fund industry and one of the world’s most prominent philanthropists. From his native Hungary to his adopted America, the forces of nationalism and populism are battering the liberal democratic order he has tirelessly supported. The man once described as the only individual with a foreign policy must contend with the rise of strongmen across the globe — and a vicious backlash designed to delegitimise him.