There are contentious figures in history, and then there is the revolutionary leader Ernesto “Che” Guevara, whose name still provokes passion and fury in equal measure, more than four decades after his death. Guevara qualified as a doctor in 1953, at the age of 25, but within a few years he was a fully fledged Marxist guerrilla, storming Cuba under Fidel Castro’s leadership, helping to overthrow that country’s dictator and bring Castro to power in 1959. Less than a decade later, Guevara was killed by the CIA while implementing a revolution, in Bolivia. His actions in between ensured that many would regard him as a hero who dared to resist American hegemony, while others deplored him as a brutal tyrant who approved the execution of prisoners without fair trial.

So, any film-maker who dabbles in Guevara’s life story is asking for trouble. Nonetheless, when Walter Salles’s compassionate, beautifully shot film The Motorcycle Diaries was released in 2004, it seemed likely that it would be insulated from controversy by dint of focusing exclusively on Guevara’s pre-Che days. The action is restricted to the nine-month journey across Latin America undertaken in 1952 by the young Argentine medical student (played by Gael Garcia Bernal) and his friend, the biochemist Alberto Granado (Rodrigo de la Serna), partly on a Norton motorcycle nicknamed “the Mighty One”.

The experience is credited with politicising the future revolutionary and opening his eyes to the suffering and injustice around him. Significant stops on his journey included the Chuquicamata copper mines, where the film shows him berating the foreman for his mistreatment of poor migrant workers, and a leprosarium in the Amazon rainforest, where the men tended to patients for several weeks. Jose Rivera’s screenplay is based on accounts by the men themselves: Guevara’s memoir, which he wrote some years after the trip, and Granado’s Back on the Road: A Journey through Latin America. Salles also hired as artistic supervisor the Italian journalist Gianni Mina, the European editor of Guevara’s book. How could anyone take issue with such an authoritative pedigree?

It was perhaps inevitable that the film would attract objections from commentators unhappy that this idealised portrait of the young Guevara was not placed in the context of his later hubris and cruelty. Anthony Daniels, author of Utopias Elsewhere and Monrovia Mon Amour, observed that the film “relies for its effect upon the fact that audiences will all know a minimum about Guevara: for example, that he was a social revolutionary who died in the jungles of Bolivia, and never made a penny for himself. But they will otherwise know little of his actual opinions or actions, and will not have read his tedious and inflexibly dogmatic speeches and writings. It is as if someone were to make a film about Adolf Hitler by portraying him as a vegetarian who loved animals and was against unemployment. This would be true, but again would be rather beside the point”.

In fact, Rivera consciously avoided any kind of contextualising, even when such opportunities presented themselves. “There’s a scene in the diary that I wrote in the first draft of the screenplay,” he said, “where Ernesto is getting an asthma attack, and he’s on the boat in the Amazon, and somebody in the crowd gives him a cigar to smoke, saying, ‘This will be good for your asthma.’ I loved it, and put it in, then I thought, ‘It’s gonna seem like too much — “Oh, there’s Ernesto’s first cigar!”’ When you have a story of a man of such weight, every little detail could add too much weight to the film.”

If The Motorcycle Diaries is guilty of anything, it is of being too soft on the mythology of Che Guevara. Certainly, this is not a movie that has room for foibles, or for the kind of observations Guevara made in his diary after passing through a barrio in Caracas: “The blacks... have conserved their racial purity by a lack of affinity with washing,” he wrote. “The black is indolent and fanciful, he spends his money on frivolity and drink.” The weather would turn decidedly nippy in hell before we got to hear Garcia Bernal speak lines such as those in a film executive-produced by Robert Redford.

Critics at the time of the film’s release were not blind to its elements of hagiography. “From the start, in contrast to the carousing Alberto, Ernesto is almost poetically sensitive,” wrote Peter Rainer in New York magazine. “Even his asthma attacks symbolise a kind of romanticised frailty uniting him with the sick and the poor.” Jessica Winter, in The Village Voice, derided the film as “a lavishly illustrated Rough Guide to white liberal self-affirmation”.

Do these faults actually render the movie bogus? There are certainly those who believe the trip itself never even took place, at least not in the form described on page or screen; after all, Guevara was no slouch when it came to self-mythologising, and The Motorcycle Diaries could be seen as providing an all too convenient narrative bridge between Ernesto Guevara and the mighty, reborn Che. If, however, one accepts that the men did cross South America together, then the script mostly sticks to the journey as recorded. One could quibble with points of emphasis: does the camera need to linger quite so gratuitously over a shot of Guevara insisting, against medical advice, on shaking the hand of a leper? It’s regrettable, too, that Salles inserts monochrome tableaux of the noble poor staring at the camera, in the manner of a TV charity appeal.

The good news for sticklers, though, is that only one part of the film departs dramatically from the source material. The bad news is that it’s arguably the most important scene: the climax. In this, Guevara leaves the party the doctors at the leprosarium have thrown for his 24th birthday and swims across the Amazon, in the dark, to the opposite shore, where the lepers are segregated. It’s a powerful scene, the film’s Rocky moment. Only it didn’t quite happen like that. In real life, he completed the crossing one bright afternoon a few days after his birthday. And while on film this doesn’t take much longer than a quick length at the swimming baths, it actually took Guevara two hours to reach the distant bank. What’s more, he arrived some miles from where the lepers were staying; had they formed a welcoming party to cheer and congratulate him, as they do in the film, they would have been sorely disappointed.

Asked to explain how an episode that warrants a sentence or two on the page had ballooned into a fully fledged set piece, Salles said: “Guevara had a certain timidity sometimes in talking about himself, so you would have to listen to Granado talking about the importance of that more than in the book itself, where it’s pretty compact.”

That crossing of the river is intended to symbolise Guevara’s allegiance to the poor and disenfranchised, but Daniels points out that, in reality, Guevara “swims the river more as an athletic feat than as a political gesture. In other words, the film manipulates the books, which themselves are not unmanipulative, to make its point”. Yet Salles’s decision to inflate this incident speaks, I think, of the need to manufacture an uplifting end to an episodic story, rather than anything more sinister. Historical drama is notoriously prone to extravagant distortion. In this context, the well-meaning errors and conflations of The Motorcycle Diaries surely rank as only the mildest of misdemeanours.

Alex von Tunzelmann, historian and author of Indian Summer: The Secret History of the End of an Empire, believes it’s instructive to compare the film with Steven Soderbergh’s recent two-part Che. “The problem with Che wasn’t really too much accuracy, but the wrong sort of accuracy,” she says. “Guevara was a serious-minded writer, but, even so, his memoirs give a strong sense of his character and those of his comrades. Soderbergh excluded the human side of these characters almost completely, in favour of what was little more than a re-enactment of military events.

“The Motorcycle Diaries is far better, because it functions as a film whether or not you know who Che is or have any interest in him as a historical figure. It makes an attempt to understand him as a three-dimensional human being, which is obviously more interesting than just listing his achievements. A straightforward timeline of events is more suitable to an encyclopedia article or a CV than to a feature film.”

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