Critics may be questioning its historical accuracy but Peter Conradi, co-author of the book that sparked the Oscar-nominated The King's Speech, argues the main point of the movie is the relationship between King George VI and the man who helped conquer his stammer.
The knives are out for The King's Speech, the film about King George VI's lifelong battle with his stammer that's leading the race for this year's Oscars, with 12 nominations. Critics and audiences across the world love this royal tale of triumph over adversity especially the portrayal of the troubled monarch by Colin Firth, already crowned with a Golden Globe for his efforts.
With less than a fortnight to go before the Oscars ceremony, however, director Tom Hooper is being taken to task for playing fast and loose with the facts.
British historian Andrew Roberts set the ball rolling after the film's release in America in November, describing it as worthless as history because of its addiction to long-exploded myths.
Commentator Christopher Hitchens, no friend of the British royal family, claims it perpetrates a gross falsification of history, while Martin Filler of the New York Review of Books took Oxford-educated Hooper (who apparently read English rather than history) to task for ignoring the fact his royal hero was described by contemporaries as a nitwit and moron.
Much of this fire has been directed at the film's handling of the events of December 1936 when King George, known as Bertie to his family and now to film-goers, reluctantly assumed the throne after his elder brother, Edward VIII, abdicated to marry Wallis Simpson, a twice-divorced American.
In the film, Winston Churchill, the future Prime Minister, is a staunch supporter of Bertie. In reality, he spoke out in the House of Commons in favour of Edward VIII, doing considerable damage to his own career in the short term.
While the transformation of such a well-known figure as Churchill into a one-dimensional supporter of our tongue-tied hero appears to have been deliberate, there were other unintentional slips, picked up by film buffs and dutifully reported by the British media. For example, the present queen's late sister is referred to as Margaret rather than Margaret Rose; a Tiger Moth flown by Edward VIII in 1936 bears a registration number that did not exist until 1941; while the women wore seamless stockings, an innovation that would not reach Britain until after the war.
And then there are the alleged sins of omission, in particular the way The King's Speech skirts around the tricky subject of the royal family's support for the policy of appeasement towards Nazi Germany pursued by Neville Chamberlain, prime minister on the outbreak of war.
Several weeks ago, talk began to circulate on the internet of a letter George VI wrote to Lord Halifax, the foreign secretary, early in 1939, expressing his hope that Jews desperate to get out of Germany would be barred from doing so. The flagging up of the letter, it was claimed, was the work of supporters of rival Oscar contenders hoping to turn the Academy - in particular, its many Jewish members - against the film.
It is up to Hooper and David Seidler, his screenwriter, to justify their decision to change the facts. If they care to, that is. After all, this is a docudrama rather than documentary. Devotees of the latter will not have to wait long: Britain's Channel 4 is planning to screen one a few days after the February 27 Oscars, with others likely to follow.
But what about the film's central point: the relationship between Bertie and Lionel Logue, his iconoclastic speech therapist?
As co-author of a book telling the true story behind the events that inspired the film, I was pleased to see The King's Speech fares much better on this count thanks, in part, to Logue's diary and the cache of other documents that Mark Logue, his grandson and my co-author, made available to Hooper.
The diaries themselves provide a rich insight into what went on behind closed doors. Firth's portrayal of Bertie and his impediment, for example, was informed by the card Logue filled out after his first meeting with his royal patient in October 1926, at which he noted, among other things, his poor use of his diaphragm and "very flabby waistline".
The scene in which the director cuts backwards and forwards between the then Duke of York's treatment and his public speeches reflects the sheer number of meetings they had in the early years: 82 between October 1926 and December 1927.
Some of Logue's most telling insights, however, come from World War II, which lies beyond the period covered by the film - which ends with the monarch's speech on the evening of September 3, 1939. He provides us with colourful fly-on-the-wall accounts of Christmases with the royal family at Windsor and Sandringham, which were always spoilt for the King, who had to leave his lunch of boar's head and prunes (well, there was a war on) to make his afternoon broadcast to the empire.
Even here, Seidler has resorted to his imagination, often because there is no alternative. Logue's own writings provide the sole account of his many meetings with his royal patient, which necessarily makes for a one-sided account of what went on in the privacy of the consulting room. He was strangely reticent when it came to detailing the treatment he prescribed.
Sadly, I did not come across any real-life evidence for the screen Logue's encouragement of the king to use a string of swear words to help free his tongue.
Nor were the two men as matey in reality as the film suggests: when the speech therapist writes to the king, he calls him "Your Majesty", although he gets a "My dear Logue" in return. There's no lese-majesty here. Yet within the confines of the day, there was no doubting the closeness of their relationship. A gift every year of a book to his royal patient on his birthday was always rewarded with a thank you note.
And what of the future King George VI's stammer? It was certainly not as extreme as in the opening scene of the film, where he is shown literally lost for words as he addresses the crowds at the Empire Exhibition in Wembley in 1925.
"Bertie got through his speech all right," his father, George V wrote to his fourth son, Prince George, the next day, adding, "but there were some long pauses."
There was no doubt, however, that Wembley was the catalyst for Bertie's decision to consult Logue. Nor that his stammer was to remain a problem for many years after, as was demonstrated by the monarch's decision to renew his contact with the Australian, after a pause of several years, once he came to the throne in December 1936.
The few recordings of the king that have survived, among them the outbreak-of-war speech that forms the climax of the film, contain pauses that are clearly not deliberate.
And these recordings may overstate his fluency. Among the more curious documents that have emerged in the wake of the film was a letter written by David Martin, a former BBC engineer who, as a 19-year-old, was given the task of editing out stutters and pauses from the king's Christmas speeches before they were broadcast across the Empire, apparently on the direct orders of Churchill.
"There were many millions of British [citizens] throughout the world, all part of what was the British Empire, who looked to London for leadership, guidance and encouragement," Martin wrote in a letter to his family before his death two years ago.
"If the speech was broadcast just as the King delivered it, it would have given a very bad impression of what things were like in the Motherland. How wise of the Prime Minister to have given his instruction at that time in our history."
The King's Speech: How One Man Saved The British Monarchy, by Mark Logue and Peter Conradi (Quercus $36.99).
The King's Speech is in cinemas now.