In 1858 Longwood House and The Valley of the Tomb were handed over to the French State, then headed by Napoleon's nephew, Napoleon III. The French paid £7,100 for the properties. A condition of the transfer was that the French Government should appoint a representative responsible for their upkeep.
Some background on this decision may be interesting.
By the 1850's Longwood House had been badly neglected, and was being used for agricultural purposes. The Valley of the Tomb remained a popular tourist destination even though Napoleon's body had been removed in 1840, and there was talk that P.T. Barnum would buy it, obviously for its commercial potential.
This was a time of Anglo French entente: Britain and France had just fought as allies in the Crimea, and Napoleon III and the Empress Eugenie had developed a close friendship with Queen Victoria.
In 1855 Queen Victoria visited Paris, the first visit of a reigning English monarch to France since 1431.
She wrote about her trip to her cousin, Leopold II, King of the Belgians:
Our reception is most gratifying - for it is enthusiastic and really kind in the
highest degree, - and Maréchal Magnan ... says that such a reception as I have received every day here - is much greater & much more enthusiastic even than Napoléon on his return from his Victories had received.!!
During her visit in 1855 she took the young Prince of Wales (later Edward VII) to Les Invalides, where Napoleon's body had rested since 1840, and bade him "Kneel down before the Tomb of the Great Napoleon". This was a very big change in official attitudes from 1821 when Hudson Lowe had refused to allow the single word "Napoleon" to be inscribed on the tomb!
The French Consul has some very good cartoons and pictures from an exhibition on the Congress of Paris (1856) which provide added backround on this period French Consul's Blog 18th Feb 2008
As a footnote it should be noted that Napoleon III died in exile in England, and his son died in 1879 fighting in the British Army against the Zulus. The body of Napoleon III, his son, and that of the Empress Eugenie (who died in 1820) are buried in the Imperial Crypt at Saint Michael’s Abbey, Farnborough Hampshire. There has been some talk about moving their bodies back to France.
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