Richard J Evans: Is this the past as we know it?

Telling a good story - the only way to ensure that a film makes good profits- will always win out over historical accuracy

History is suddenly all around us. Go to the cinema or turn on your TV set, and you are as likely as not to find the past being presented to viewers and listeners as the present. But is it the past as historians know it?

History is suddenly all around us. Go to the cinema or turn on your TV set, and you are as likely as not to find the past being presented to viewers and listeners as the present. But is it the past as historians know it?

Were things in ancient Rome really as bad as they are made out to be in Gladiator? Was the American War of Independence really fought the way it was by the villains Mel Gibson was up against in The Patriot? Did the Allies' capture of the German Enigma encoding machine really happen the way it did in U-571? Is the portrayal of snipers at the Battle of Stalingrad in the new film Enemy at the Gates warranted in any way by the evidence we have for what happened in the real battle? Will Kevin Costner's forthcoming Thirteen Days be true to the Cuban missile crisis of 1962?

Do documentaries on the Nazis concentrate on the central issues, or do they waste their time on trivialities like Hitler's sex-life?And how reliable is Simon Schama as a guide to our nation's past?

Enough has been said about recent Hollywood portrayals of the past to convince plenty of people that it didn't happen that way at all. The Emperor Commodus, villain of the piece in Gladiator, certainly spent a lot of time fighting in the arena, but far from dying at the hands of a rival, all the historical evidence seems to agree that he was poisoned by his mistress. The British forces in the War of Independence did not behave in the way The Patriot's German director has them behaving - like the Waffen-SS on the Eastern Front in the Second World War. Plenty of Americans fought on the British side; and plenty of Americans on the rebel side had slaves, though you would never guess so from the movie. As almost everybody knows, the Enigma machine was captured by the British, not by the Americans. And the German sniper we see confronting his Soviet counterpart in Enemy at the Gates never existed.

All of this is clear enough. Do people who go to see these films actually take them as the truth about the past, especially when they are labelled as "based on a true story", or in a slightly more up-front admission of its distance from historical reality, "inspired by a true story"?

Hollywood now has a formidable ability to recreate the feel of a past epoch of human history with the aid of advanced prosthetics, computer-generated images, and detailed historical research. Costumes, settings, battles, props are now more likely to be authentic - or at least, to look authentic - than in the time of Cecil B deMille. The days are long since gone when Sam Goldwyn could tell a researcher who informed him that there were only 12 vestal virgins in ancient Rome, and most of them were very old, that he would have 100 of them on the set, all nubile and scantily clad, and damn the research.

Telling a good story - the only way to ensure a film makes good profits - will always win out over historical accuracy. Asked by a professional historian whether the movie industry had a responsibility to get the story right, the film director John Sayles replied candidly: "I think using the word 'responsibility' in the same sentence as 'the movie industry' just doesn't fit". When Alan Bennett wrote The Madness of George III (filmed, famously, under the title The Madness of King George, because otherwise cinema-goers in the US would wonder what had happened to the first two parts of the trilogy), he tweaked the historical material because otherwise it would all have been rather boring. And just showing a sniper on the Soviet side at the Battle of Stalingrad wouldn't have made for a watchable movie.

Directors sometimes get professional historians to act as advisers for films, but they seldom listen to their advice. A colleague of mine was paid to go over an episode of The Young Indiana Jones for historical inaccuracies. When she pointed a few out, she was told they couldn't be altered. Could her name be removed from the credits then, she asked. No, she had signed a contract that said it would be there. But, she was told, the credits would roll up very fast, so nobody would notice her name anyway.

In the end, people may accept the accuracy at least of the backing for a self-evidently fictional drama like The Patriot or Gladiator, at least while they're in the cinema. Once they come out, however, do they really accept the story? Who believes the version of President Kennedy's assassination purveyed in Oliver Stone's JFK, for instance? It's fun to watch, like all these films, not least because it seems so authentic. But perhaps, after all, we are underestimating the audience if we think they really buy the story as true. People watching The Madness of George III will accept that George III was mad; they may even accept that he underwent the ghastly treatments depicted in Alan Bennett's play. But the chances are that they will be intelligent enough to know that not all of it happened exactly that way, and the words the king speaks are Bennett's as much as his. None of this diminishes one's pleasure in seeing the play or the film that was based on it.

And if people really want to find out, the play or film may lead them to read what historians have to say about it all. Gladiator has inspired exhibitions and books that offer a look at the historical realities. This suggests that more people can tell truth from fiction than we might suppose. If Enemy at the Gates inspires a fraction of its audience to pick up and read Anthony Beevor's marvellous book about Stalingrad, that will all be to the good.

Things are different when it comes to avowedly documentary presentations of history (or "the new gardening" as they call it at the BBC) on TV. Here, the whole point lies in the historical accuracy that such programmes aim to purvey. Here the story definitely comes off second-best. The past few years have seen some unprecedentedly intelligent and well-made historical documentaries presented on UK television. Lawrence Rees's series The Nazis: A Warning from History was a particular high point. True, there was next to nothing in the series to justify the subtitle. No warning was issued. As an accurate and intelligently argued presentation of the Third Reich, however, it was hard to fault. It put across some subtle and complex interpretations of Nazi Germany without in any way trivialising its daunting subject.

More recently, there has been Simon Schama's gripping history of Britain to marvel at. Deprived of film footage, his portrayal of medieval England depends heavily on his way with words, and Schama's gift of the gab proves irresistible in holding the viewers' attention and convincing them that medieval England was not so incomprehensible after all. Inevitably this involves a good deal of simplification and drastically underplays the strangeness of the past. Yet it doesn't cross the real - and important - line between fact and fiction in any significant way. And in the end, like the Hollywood movies, TV documentaries too can serve to lead viewers on to explore history further, and that, surely, can't be all bad.

The author is Professor of Modern History at Cambridge University. His book 'In Defence of History' has just been reissued by Granta Books