On 1 March 1815, Napoleon landed at Golfe-Juan, to the east of Cannes. He had been exiled on the island of Elba, but slipped away on board the brig Inconstant with some 1000 men. Thus began the Hundred Days, in which Napoleon reigned again but was defeated at the Battle of Waterloo.
Right after the news of Napoleon's landing shocked Europe, William Playfair claimed he had reported Bonaparte's design to Earl Bathurst (Wikipedia), Secretary of State for War and the Colonies, and Comte De la Chatre (Wikipedia), French ambassador in England, but was given a cold reception.
It was published in a 33-page pamphlet:
William Playfair (1815), A Statement, which was Made in October, to Earl Bathurst and in November, 1814, to the Comte De la Chatre, the French Ambassador, of Bounaparte's Plot to Re-usurp the Crown of France (Google; also found in one of volumes included at Google).
William Playfair (Wikipedia) was a Scottish engineer and political economist, who also served as a secret agent during the war with France. (Playfair tells of himself as "for more than twenty years, I have employed such abilities as I am possessed of, in support of the cause in which the country fought, without asking any reward from Government").
A Statement describes how Playfair reported Napoleon's plot to regain the French throne but was met with neglect.
On 10 September 1814, Playfair dined in London with an Italian named Caraman and a witness, Thomas Byerley (p.8).
Caraman had been a French conscript. He was one of Napoleon's guard in Elba, but, for private reasons, left him and was going to Sweden. Playfair accidentally got acquainted with him, and asked him to dine at an Italian eating house near Leicester Square. Caraman believed Playfair was Napoleon's admirer, and Playfair "had no wish to undeceive him." (p.11)
Playfair learned of "Buonaparte's cipher and the key" among others. He was given some papers, including one covered on the back with green silk, containing "a table of letters curiously disposed", and another containing "Buonaparte's address to Frenchmen in cipher." Byerley copied them (because the originals had to be returned), and they jointly deciphered the address with the key Caraman had told Playfair. (p.9)
When Playfair pointed out that it was unlike Buonaparte to disclose his plans, Caraman explained that the situation is different from the time when he was Emperor, when he was obeyed the moment he spoke. (p.11)
Playfair thought the Allied Powers had to change his treatment while the Congress in Vienna was sitting. (p.13)
In October, Byerley wrote to the French ambassador, Count La Chatre, and was given an invitation for Playfair. Playfair did not act right after 10 September because he had promised to Caraman not to disclose it till he had time to be in Sweden (Why this precaution, if Caraman believed Playfair was Napoleon's admirer? Was Caraman aware that he was disclosing information that he should not?), and also because there was no urgency in view of the Congress. (p.10) (The plot was expected to be carried out after the Congress, when the armies are withdrawn and partly disbanded (p.12).)
On 3 November 1814, a Mr. Morier on behalf of Bathurst received Playfair at the Foreign Office, but Morier was cold ("most forbidding"), and uninterestedly called the cipher table a "conundrum", and did not show any interest to know its use (p.14-15).
Playfair also contacted the French ambassador, La Chatre. Jonville, on behalf of the latter, thanked for the letter and the cipher (p.16), but did not appreciate the meaning of his call (p.17).
Upon hearing the news of Napoleon's escape from Elba, Playfair presented the papers to the publisher, J. J. Stockdale (Wikipedia) with a letter dated 25 March 1815 (p.3).
Playfair explains one reason of making this disclosure was "I am resolved not to pass for an impostor. To vindicate myself from false suspicion, is my first reason." (p.3) According to Boyce (1816) (p.81), the minister informed of the plot communicated the secret to one of the agents of the police, who, however, being a Buonapartist, made arrangements so that nothing was brought against his accomplices, and the informer was branded as an imposter.
The following is the text of "A Proclamation in Cipher from Buonaparte to the French Army a Copy of which was in the Hands of one or more Persons in almost every Regiment in the Service." (p.21 ff.)
This is deciphered as follows.
The enciphering scheme is a Porta-like polyalphabetic cipher based on the following pairing table, with a key "La France et ma famille."
A | a b c d e f g h i k l m|
B | z n o p q r s t u w x y
C | a b c d e f g h i k l m|
D | z n o p q r s t u w x y
E | a b c d e f g h i k l m|
F | y z n o p q r s t u w x
G | a b c d e f g h i k l m|
H | x y z n o p q r s t u w
I | a b c d e f g h i k l m|
K | w x y z n o p q r s t u
L | a b c d e f g h i k l m|
M | u w x y z n o p q r s t
N | a b c d e f g h i k l m|
O | t u w x y z n o p q r s
P | a b c d e f g h i k l m|
Q | s t u w x y z n o p q r
R | a b c d e f g h i k l m|
S | r s t u w x y z n o p q
T | a b c d e f g h i k l m|
U | q r s t u w x y z n o p
W | a b c d e f g h i k l m|
X | p q r s t u w x y z n o
Y | a b c d e f g h i k l m|
Z | o p q r s t u w x y z n
The scheme is explained as follows.
The enciphered proclamation attributed to Napoleon was repeated in several sources in the nineteenth century.
(November 1815) Politisches Journal nebst Anzeige von gelehrten und andern Sachen, vol. 68 p.706 (Google, Google, Google)
(1816) Edmund Boyce, The Second Usurpation of Buonaparte: Or, A History of the Causes, Progress ... p.79 (Google)
(1816) Nicolson Bain, A Detailed Account of the Battles of Quatre Bras, Ligny, and Waterloo ... (Google) p.18 (Page 17 quotes from p.77 of Boyce (1816), and the following description seems to be taken from the same source.)
(1816) Magazin fur Zeitungsleser (Google)
After the contemporary quotations in the above works, the episode was described in books on curiosities rather than history.
(1853) Nouveau manuel de physique et de chimie amusantes, grande initiation a la ... (Google) p.298
(1884) Auguste Héraud, Jeux et récréations scientifiques (1884) (Google), p.541 (The ciphertext is not given. The explanation of the scheme, based on the Vigenere table, seems inaccurate.)
(1890) C.C. Bombaugh, Gleanings for the Curious, 3rd ed., repreinted in Oddities and Curiosities of Words and Literature (Dover Publications, New York, 1961) p.292
(?) Curiosidades para los estudiosos[?] (Universidad Autonomad Nuevo Leon) p.49
When Napoleon landed at Golfe-Juan on 1 March 1815, he issued proclamations to the Army and the French people.
The proclamation to the army dated 1 March 1815 can be seen at Gallica (in one column; from Collection de Vinck at BnF), Images d'art (in two columns; this seems to be a copy preserved at musée des châteaux de Malmaison et de Bois-Préau), Paris Musées (in one column; Musée Carnavalet), auction site (in two columns), and Google (p.377). (An English text is found at Napoleon's Addresses (1897), Napoleon's Addresses: 1815, Napoleon the good, the Bad, and the Exiled, but somehow these are dated 5 March.)
The text of the enciphered proclamation obtained by Playfair in the fall of 1814 differs from the actual proclamation to the army issued on 1 March 1815. Googling only returns publications in the nineteenth century quoting the text disclosed by Playfair, which are either contemporary publications or books about curiosities rather than history.
It is wondered whether the message, containing no dates or names, was really worth being enciphered. Playfair says the proclamation he obtained was "in the Hands of one or more Persons in almost every Regiment in the Service" (probably as of March 1815). If so, one expects one or more copies should be extant. (The proclamation issued on 1 March 1815 is extant in several copies, as referenced above.)
At present, the only modern description of this episode known to me is Bruce Berkowitz (2018), Playfair: The True Story of the British Secret Agent Who Changed How We See the World. (I have as yet seen only its review.) Historians' advice is solicited. (According to Norwood Young (1914), Napoleon in Exile at Elba, it was a common belief that Napoleon would return when he chose, and his schemes were reported to Paris in July and in August. Still, it was at the beginning of December 1814 that Napoleon resolved to return to France (p.282-283, 285). If this narrative is correct, Playfair's warning was only one of premature reports at best.)
Sometimes, primary sources of historical ciphertexts are not firmly established. Trevanion's cipher (see another article) and Prince Charles' musical cipher (see another article) are two such examples. Is the proclamation attributed to Napoleon added to the list?
Does the cipher reveal anything about the authenticity? Playfair calls the cipher as "far superior to any in the Encyclopediae, or to be found in the British Museum" (p.24), but Playfair may have been unaware of Rees' Cyclopedia, Vol. VIII (1807), which describes polyalphabetic ciphers and the Vigenere table. If Playfair was ignorant of polyalphabetic ciphers, it is unlikely that he forged the ciphertext. What about Caraman? Today, it is known that Marie-Antoinette used the Porta-like substitution, and Napoleon himself was given such a cipher in 1798, but these facts were probably unknown to Playfair or Caraman. Unless Caraman was familiar with the sixteenth-century books of Bellaso or Porta or any other publication describing the Porta-like substitution, it would be natural to consider that his knowledge of the scheme came from Napoleon.
Additional Notes (12 January 2022): Berkowitz (2018), dealing with the episode on p.283-287, calls the story "odd." Still, he points out Bathurst's papers in Francis Bickley, ed. (1923), Report on the Manuscripts of Earl Bathurst include summaries and excerpts from three letters by Playfair dated 31 October, 3 November, and 5 November 1814. So, the overall narrative of Playfair's warning of the plot may be believed. On the other hand, it was also true that "Government has often been deceived by pretended communications and money obtained" as Playfair was aware in his letter of 5 November.
It remains a question whether the ciphertext provided by Caraman was genuine.
S. Tomokiyo, "Great Ciphers of Napoleon's Grande Armée"©2021 S.Tomokiyo