An early version of the ‘King’s Speech’ reveals Britain was preparing to declare war on Germany before Hitler invaded Poland.
George VI’s address to the nation, depicted in the 2010 movie starring Colin Firth as the stammering monarch, had been written at least nine days beforehand.
The three-page document that has come to light is entitled ‘Draft King’s Speech’ and is dated August 25, 1939.
The document, which was written on August 25, 1939 - seven days before Germany’s invasion of Poland - has come to light after 74 years.
The typed document, the second draft of the speech, was retained by civil servant Harold Vale Rhodes, who had previously written a first attempt.
In a pencilled note in the left-hand margin, Mr Rhodes criticised the length of some of the sentences in the second draft and hinted that his should be used.
It would appear his advice was followed - the final speech read to the nation and the Commonwealth by the King on September 3 contained shorter, more concise sentences.
Although the tone remained the same, some of the content was significantly different. For instance, it did not mention Germany or Hitler by name but merely 'our enemies’.
The early draft accused Germany of being a bully that wanted to dominate the world by brute force and stressed that 'we are fighting for the principles of freedom and justice'.
In the Oscar-winning film, Colin Firth's royal character was given little time to prepare for his defining address to the nation but in reality it appears the speech was being readied for him more than a week beforehand.
The rejected draft was acquired by the unnamed owner in a load of paperwork from Mr Rhodes' estate following his death in 1970.
It has now been put up for sale at auction with a pre-sale estimate of £4,000.
Dr Gabriel Heaton, of Sotheby's, which is selling the speech, said: ‘This is a fascinating document for a number of reasons.
‘It brings to life not just the speech, but a pivotal moment in British history.
‘It was written before Poland had been invaded but at a time when it was clear we were moving towards war with Germany.
He added: ‘You get a sense of the preparations for the speech and the struggle to find the right words to prepare the nation for the terrible fight that lay ahead.
‘There would have been a group of people writing this speech and Rhodes was one of them.
‘He had provided a first draft and was sent this revised version. His note in the margin is saying that his original is better than this one and that the wording should be shorter.
Nigel Steel, a historian at the Imperial War Museum, said: ‘When it happened, war wasn't out of the blue.
‘There had been a number of political crises involving Germany going on for over a year before.