In the run-up to D-Day, a French soldier exiled in London was given the task of telling his compatriots how they should react once the liberation of their country began, reports the BBC.
On 31 May 1944 Jean-Louis Cremieux-Brilhac sat in his study at 17 Hill Street Mayfair, and typed out the D-Day orders for the people of France.
These were the instructions to be read over the French service of the BBC, telling the population how to react once they learned the Allies had landed.
The document - four pages of flimsy paper marked "secret", type-written with annotations in pencil - has been in Cremieux-Brilhac's possession ever since.
Now aged 97 and living in Paris, he recalls with perfect clarity the excitement of the time.
"I was secretary of the Free French Propaganda Committee. There were five or six of us, and my job was to draw up the D-Day orders taking account of our discussions earlier in the day.
"We knew that the invasion was coming but of course we did not know exactly when. We had to be ready."
The instructions were intended "for all French men and women not organised in, or attached to, a Resistance group".
Read more of this report from the BBC.