The Hour: Past imperfect

Did they really smoke that much? Could Freddie really have afforded such a dapper cut of tweed? And how, exactly, did Bel get her hair quite that shade of honey blonde? Tonight, as audiences take in the first episode of the BBC's much-discussed drama The Hour, historians will once again commence battle over just how accurately period Britain has been portrayed. The show has a lot to live up to; billed as the "British version of Mad Men", comparisons with Matthew Weiner's famously fastidious portrayal of life in 1960s New York will be inevitable. From the type of carbon paper carried by Peggy et al to the way Don holds his hat, Wiener insisted that every last detail be spot-on.

Accuracy is all too often disregarded when it comes to the creative process. In an early scene from The King's Speech, the then Duke of York, played by Colin Firth, visits a doctor in central London. Attempting to cure his crippling stutter, he's told to fill his mouth with marbles and read "a wealth of words" aloud. The result is less clear annunciation, more incomprehensible gurgling; in a rage, he scatters the glass balls over the floor and storms off.

The story, observed historians, might be gripping – but it's a long way from accurate: although another royal, Charles I, attempted to correct his speech by chomping on pebbles, there's little evidence to suggest the method endured. It's not the only point on which the film strays from the truth; throughout, director Tom Hooper has employed his artistic licence. As with the marbles, the casual relationship between "Bertie" and his speech therapist Lionel Logue is likely something of an exaggeration, though a relatively benign one. More serious, historians have observed, is the implication that Winston Churchill encouraged the future King to take over during the abdication crisis; in fact, he backed the feckless Edward to the last.

Does any of this matter? Certainly, it didn't when it came to netting audiences. As well as clocking up a string of Baftas, Golden Globes and Oscars, The King's Speech went on to become the most successful independent British film of all time, earning £3m in its first three weeks in the UK and achieving the highest per-theatre gross of the year in the US.

When it comes to the crunch, there are few things we love more than a historical drama. On the big screen, Britain's biggest hitters have all too-often come with florid prose and period costumes: think Lawrence of Arabia, Shakespeare in Love, and The Madness of King George. Meanwhile, television schedules are bursting with retro offerings – whether it's US imports Spartacus, Boardwalk Empire and The Kennedys (which saw historians, as well as the descendants of the titular family, apparently unhappy with the accuracy of the script), the chintzy comforts of Downton Abbey or the sexuality of The Tudors. Or, indeed, The Hour. "There's no doubt that we love historical dramas," agrees Dr Belé* Vidal, lecturer in Film Studies at King's College London. "There's an element of escape, of spectacle – and no matter what period it is set in, there's an expectation of character depth and storytelling." But as for the question of accuracy and its significance, opinion is very much divided.

"To me, it's largely about the 'truth claims' they make," says Dr Tim Cole, a senior lecturer in social history at Bristol University. Specialising in Holocaust studies, Cole has seen the past interpreted and re-interpreted by countless directors, producers and writers. "Some films – such as Schindler's List, for instance, which was distributed free to schools in America – make certain claims about the past. In that case, they must get things right. Others – Life is Beautiful, say – are about a narrative. Then, those small details matter less." Towards the end of Schindler's List, Cole points out, the audience is presented with an almost blameless Oskar Schindler – a kind of "perfect hero". "It's a simplification – an over-simplification; rarely are things so lacking in complexity."

Over-simplification is one of the chief bugbears for those critiquing what we watch. Part of the problem lies in the very reasons we like period pieces: nostalgia.

"Much of what becomes popular presents the past as a better, simpler place, where the divisions between good and evil are cut and dry," notes Cole. "If you look at your classic period drama – things like the Jane Austen adaptations and so on – you find that, frequently, more complex undercurrents such as class struggle or social oppression are left unexamined."

At the same time, we're not averse to projecting some of our modern expectations on to our historical heroes. Witness the ratings-friendly levels of sex and violence in Boardwalk Empire and Spartacus. Neither could be accused of airbrushing conflict out of the past – but both participate in their fair share of embellishment.

"There's a lot that is very accurate," agrees Dr Tim Lockley, reader in American history at the University of Warwick. "There are people who were really there, things that really happened. But as you often find in American series, there has been an upping of sex and violence for entertainment value."

And it's not just sex and violence that get the Hollywood treatment; frequently the cast receive their fair share, too. "The Tudors is a good example of that," observes Lockley. "By the end of his life, Henry VIII was still being played by Jonathan Rhys Meyers, and looked relatively handsome. The real king would have been considerably more repulsive." Make-up, hair products – even cleanliness – are all superficial traits that have been retrospectively applied.

But if such superficial embellishments have become routine, the extent to which they undermine the merit of the end-result is up for debate. "Certainly, when historians first examined the phenomenon of the historical drama, they would comment on things like the costumes," says Dr Jennifer Smyth, associate professor at University of Warwick. "Very often the larger picture – the emotional experience of the past – gets sidelined."

For Cole, the deciding factor is motivation. "You have to ask why the inaccuracies are there. Is it purely aesthetic – or is it ideological? I don't know if total believability is what I want on the TV. It's not an academic text. The attraction is that it offers the chance to be a bit creative. There's no need to be pedantic." On the other hand, if there is something more significant at play – if a director is attempting to get across a specific agenda – then any straying from truth can be dangerous.

"One example is The Patriot, starring Mel Gibson," points out Lockley. Set during the American War of Independence, it depicts the British engaging in levels of brutality not seen during the Revolution, including the murder of prisoners of war and the burning alive of villagers. The point, say the film's defenders, was to demonstrate the viciousness of conflict in the South – but given that screenwriter Robert Rodat had previously been accused of airbrushing British troops out of Saving Private Ryan, it wasn't hard to wonder if some kind of prejudice was at work. Commentators drew comparisons between the on-screen behaviour of the British, and specific instances of SS brutality. Were the two simply coincidence, or was Rodat attempting to draw some kind of parallel?

Prejudices can arise unintentionally, too: in drawing on secondary sources, film-makers can easily fall victim to the problem of historiography. "It's very important to interpret the source and consider the context." In basing the popular 1970s series I, Claudius on Robert Graves' book of the same name, BBC producers reinforced some of the myths it had propagated.

By the same token, "established" history has tended to be dominated by one particular type of character: the white man. It's because of this that, ironically, creative licence might in fact produce a more accurate picture of the past. "Many of the most popular period dramas have focused on the role of women," notes Smyth of this. "Whether it's Gone with the Wind, Wuthering Heights or Upstairs, Downstairs, they show a side of life that isn't necessarily represented in strict historical accounts." The result is that such popular productions have attracted scorn for not being "real" history, while offering a sort of social history that we might not otherwise be able to access.

The question of accuracy, then, is a double-edged sword. Disregard it entirely and we risk undermining projects' credibility – particularly those that are held up as some kind of authority. But take it too seriously and it can be stifling, restricting the scope of subject matter, inhibiting narrative development and limiting aesthetics. Without employing creative licence, writers and directors would be forced to neglect whole tracts of undocumented experience – a loss to our entertainment, yes, but also our understanding.

The Hour starts tonight on BBC Two at 9pm

Super bloopers

Downton Abbey (2010 –)

Modern street signs, television aerials and double yellow lines have all been spotted by viewers. A character using the term "boyfriend" was deemed by some fans of the show as a modern word too far on online forums.

The Young Victoria (2009)

Pity the wardrobe department charged with creating garments for this take on the early years of Queen Victoria's rule, which began in 1837. Many of the costumes have visible zips – which weren't invented until 1851.

Mad Men (2007 –)

A sharp-eared (and eyed) fan of the show noticed that a record played at a Christmas party was the right era (1964) but in a 1970-issue sleeve. Another spot was a three-volume dictionary that only came into existence in the 1980s.

The Tudors (2007 – 2010)

As well as Henry VIII's inaccurate waist size, this series played fast and loose with regal language. One episode saw the king complain that the French were "messing him about" while one character refers to court as a "meat market".

Braveheart (1995)

Movie-goof geeks have had a field day with Mel Gibson's Scottish epic. Cars, watches and trainers have been spotted in battle scenes, while wobbly weapons make fight scenes less authentic. Extras with dental fillings have also had critics up in arms.