The regalia used for Emperor Napoléon I’s and Empress Joséphine’s spectacular coronation in 1804 were nearly all destroyed following the downfall of the First Empire and the restoration of the Bourbons. Despite reintroducing the Empire in 1852, Napoléon III never got around to be crowned, but for the Universal Exhibition which was held in Paris in 1855 he ordered crowns to be made for himself and Empress Eugénie.
The Emperor’s crown, which judged by its representation in contemporary paintings had a similar form, has since been lost, while the Empress’s crown is to my knowledge the only preserved crown of a French consort.
Executed by the imperial court jeweler Alexandre-Gabriel Lemonnier, assisted by J.-P. Maheu, Auguste Fannière and Joseph Fannière, it is made of gold adorned with 2,490 diamonds (1,354 brilliant-cut and 1,1136 rose-cut diamonds) and 56 emeralds. The small crown, which is 12.5 centimetres high and has a diameter of fifteen centimetres, was based on the crowns featured in the arms of the First as well as the Second Empire. The most obvious symbolism is the eight imperial eagles situated between the crown’s arches.
As she was not crowned, Empress Eugénie apparently never actually wore the crown, but it was used ceremonially and also appeared in paintings, such as Franz Xavier Winterhalter’s famous state portrait of the Empress (detail above).
While a large amount of the Crown Diamonds was used for the Emperor’s crown, only a few were used for the Empress’s crown. Thus the crown was apparently deemed private property and following the downfall of the Second Empire in 1870 it was restored to the widowed ex-Empress by the French Republic.
The ex-Empress outlived the Empire for no less than fifty years, dying in Madrid in 1920, aged 94. I believe the crown was inherited by her goddaughter, Countess Louise-Eugénie von Moltke-Huitfeldt, née Patterson-Bonaparte, whose descendants later sold it.
The crown was presented to the Louvre by Mr and Mrs Roberto Polo in 1988 and is now exhibited in the Apollo Gallery.