Napoleon's letter of surrender following the Battle of Waterloo is to go on display at Windsor Castle in January 2015 to mark the battle's 200th anniversary.
It was written on July 13, 1815 and is addressed to a young George IV, who is referred to as: "most powerful, the most constant, and the most generous of my enemies."
Kate Heard, of the Royal Collection Trust, commented: "It is very exciting to be able to display both these letters [the collection includes a letter to George from the Duke of Wellington] as part of the Waterloo at Windsor exhibition.
"These vivid and important documents provide a fascinating insight into the minds of the Duke and the Emperor almost directly after the Battle of Waterloo."
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