Running a high-profile arts festival – especially one affected by political and budgetary concerns – is inevitably onerous. Moritz de Hadeln, who has died aged 85, managed it with varying degrees of success not once but five times, with events in Nyon and Locarno in Switzerland, Berlin, Venice and Montreal. The first of these he founded as Visions du Réel, and it was for many years one of the premier documentary festivals in the world.

During the mid-1970s, De Hadeln was invited to take over the Locarno film festival, and passed over control of the Nyon event to his wife, Erika von dem Hagen, whom he had married in 1968. In record time, he transformed the fairly staid festival in southern Switzerland into one of the most controversial events in the movie calendar.

In 1979 De Hadeln was appointed director of the Berlin international film festival, a job he held for just over 20 years until in 2000 he was told – to his bitter response – that his contract would not be renewed: the February 2001 festival he was then preparing would be his last. The resultant furore stemmed partly from De Hadeln’s outspoken reaction and decision to take the matter to the German courts, plus a refusal to have the name of his successor mentioned in the festival offices or to meet with the future director to help ensure a smooth handover.

Born in Exeter, a year after the second world war started, Moritz had a somewhat complicated background and upbringing. His father, Harry, was a British army officer, and his mother, Alexandra (nee Bălăceanu), was a painter and sculptor. Moritz was educated throughout Europe and remained British until, in his 50s, he adopted Swiss nationality – a decision he later claimed to “deeply regret”.

After abandoning his studies at the Sorbonne in Paris, he freelanced as a photographer and short-film-maker, subsequently working as an editor for the French director Yves Allégret and at film studios in Berlin.

His next step was the founding of the Nyon international documentary film festival in 1969 and then transforming Locarno with open-air screenings of movies such as Derek Jarman’s Sebastiane, Jack Hazan’s A Bigger Splash and Walerian Borowczyk’s The Beast. These piazza screenings caused consternation among locals, many of whom watched the films from the balconies of their apartments and complained later, and the local authorities, as did the packed screenings of Pier Paolo Pasolini’s Salo, or the 120 Days of Sodom, then banned in Switzerland.

De Hadeln’s move to Berlin followed a year after the change of date from summer to February, which allowed it to anticipate the May Cannes film festival. He capitalised on this by offering a European launch for commercial movies, especially those from America that were nominated for the Oscars. Stars and directors were tempted to Berlin as part of their publicity tour before the films’ releases, and the festival gained enormous momentum.

This seeming reliance on Hollywood did not endear De Hadeln to the local film-makers and his inability – or unwillingness – to master German, saying that it was a chore for him compared with French (which he spoke with his wife), English or Italian, also provoked criticism. Certainly he was more highly regarded outside Germany, receiving innumerable awards and honours, including the Order of the Arts and Letters of the French Ministry of Culture, of which he was especially proud.

He supervised the festival during the reunification of Germany, including the transfer to lavish headquarters in Potsdamer Platz in East Berlin. His determination to expand the event meant that by the 50th festival professional participants numbered 15,000, and the audiences were numbered in hundreds of thousands.

But the authorities decided that it was time for a change. Speculation was widespread. De Hadeln’s autocratic style and insistence on working so closely with his wife – she was head of protocol – had become increasingly resented, and politically he courted controversy. At his farewell speech, given in English, De Hadeln made his feelings explicit, noting that he had left the festival in good working order, adding that what his successor – whose name he mispronounced – made of it was “his own business”.

In the spring of 2001 he and his wife formed a film consultancy business in Berlin, where they kept a base, as well as a home in Gland, Switzerland. To the surprise of the film business, De Hadeln was asked to head the Venice film festival. He was the first non-Italian to hold the position, but luckily spoke the language and had kept up his contacts. Even so his tenure was brief, lasting only for the Augusts of 2002 and 2003. There was considerable controversy during his stay, but Venice has seldom been free of that.

Even more surprisingly, a decision was made to launch a new film festival in Canada, where three major events were already held annually in Toronto, Montreal and Vancouver. The new one, the Festival Internationale du Films de Montréal, was set up in direct opposition to the existing one, with De Hadeln as director.

He rounded up many of the consultants from his Berlin heyday and with his wife set about launching the festival in 2005. There were disputes from the beginning and the programme – inevitably concentrating on French films – did not prove a success. It was held just once and in early 2006 its offices were closed. Even so it made De Hadeln unique in the specialist history of film festivals in having masterminded five of them.

Erika died in 2018.

• Moritz de Hadeln, film festival director, born 21 December 1940; died 4 July 2026