Charles-Geneviève-Louis-Auguste-André-Timothée d'Éon de Beaumont (5 October 1728 – 21 May 1810), usually known as the Chevalier d'Éon, was a French diplomat, spy and soldier, whose first 49 years were spent as a man, and whose last 33 years were spent as a woman. From 1777, d'Éon claimed to be anatomically a woman, and dressed as such. Doctors who examined the body after d'Éon's death discovered that he was anatomically male. He is considered to be one of the earliest openly transvestite or transgendered people.
Early life 
Chevalier d'Éon de Beaumont was born at the Hôtel d'Uzès in Tonnerre, Burgundy, into a poor but noble family. His father, Louis d'Éon de Beaumont, was an attorney and director of the king's dominions, later mayor of Tonnerre and sub-delegate of the intendant of the généralité of Paris.  His mother, Françoise de Charanton, was daughter of a Commissioner General to the armies of the wars of Spain and Italy. Most of what is known about d'Éon's early life comes from a partly ghost-written autobiography, The Interests of the Chevalier d'Éon de Beaumont.
D'Éon excelled in school, moving from Tonnerre to Paris in 1743, graduating in civil law and canon law from the Collège Mazarin, in 1749 at age 21. D'Éon became secretary to Bertier de Sauvigny, intendant of Paris, served as a secretary to the administrator of the fiscal department, and was appointed a royal censor for history and literature by Malesherbes in 1758.
Life as a spy 
In 1756 d'Éon joined the secret network of spies called the Secret du Roi which worked for King Louis XV personally, without the knowledge of the government, and sometimes against official policies and treaties. The monarch sent d'Éon with the Chevalier Douglas, Alexandre-Pierre de Mackensie-Douglas, baron de Kildin, a Scottish Jacobite in French service, on a secret mission to Russia in order to meet Empress Elizabeth and intrigue with the pro-French faction against the Habsburg monarchy. D'Éon disguised himself as a lady Lea de Beaumont to do so, and even became a maid of honour to the Empress (although there is no documentary proof of d'Éon being sent on this mission). At the time the English would only allow women and children across the border into Russia in an attempt to prevent the French from reaching the Empress, since the French and English were at odds with each other. Given the delicate nature of the spy work, d'Éon had to convince the Russians, the English and even his own France that he was a woman or he would have been executed by the English upon discovery. His career in Russia is the subject of one of Valentin Pikul's novels, Le chevalier d'Éon et la guerre de Sept ans. Chevalier Douglas became French ambassador to Russia, and d'Éon was secretary to the embassy in Saint Petersburg from 1756 to 1760, serving Douglas and his successor, the marquis de l'Hôpital.
D'Éon returned to France in October 1760, and was granted a pension of 2,000 livres as reward for his service in Russia. In May 1761, he became a captain of dragoons under the maréchal de Broglie and fought in the later stages of the Seven Years' War. D'Éon served at the Battle of Villinghausen in July 1761, and was wounded at Ulstrop. After Empress Elizabeth died in January 1762, he was considered for further service in Russia, but instead was appointed secretary to the duc de Nivernais, awarded 1,000 livres, and sent to London to draft the peace treaty to formally end the Seven Years' War, which was signed in Paris on 10 February 1763. As a result of this, he was awarded a further 6,000 livres, and received the Order of Saint-Louis on 30 March 1763, becoming the Chevalier d'Éon.
Back in London, d'Éon became chargé d'affaires in April 1763, and then plenipotentiary minister - essentially interim ambassador - when the duc de Nivernais returned to Paris in July. D'Éon used this position also to spy for the king. He collected information for a potential invasion - an unfortunate and clumsy initiative of Louis XV, of which Louis's ministers were unaware - assisting a French agent, Louis François Carlet de la Rozière, who was surveying the British coastal defences. D'Éon formed connections with English nobility by sending them the produce of his vineyard and abundantly enjoyed the splendour of this interim embassy.
Upon the arrival of the new ambassador, the comte de Guerchy in October 1763, d'Éon was reduced to his former rank as secretary and humiliated by the count. D'Éon found himself trapped between two French factions: Guerchy was a supporter of the duc de Choiseul, duc de Praslin and Madame de Pompadour, in opposition to the comte de Broglie and his brother the maréchal de Broglie. D'Éon complained, and eventually decided to disobey orders to return to France. In his letter to the king, d'Éon claimed that the new ambassador had tried to drug him at a dinner at the ambassador's residence in Monmouth House in Soho Square. The British government declined a French request to extradite d'Éon, and his 2,000 livres pension was stopped in February 1764. In an effort to save his station in London, he published much of the secret diplomatic correspondence about his recall under the title Lettres, mémoires et négociations particulières du chevalier d'Éon in March 1764, disavowing Guerchy and calling him unfit for his job. This breach of diplomatic secrecy was scandalous to the point of being unheard of, but d'Éon had not yet published everything (he kept the King's secret invasion documents and those relative to the Secret du Roi as "insurance"), and the French government became very cautious in its dealings with d'Éon, even when d'Éon sued Guerchy for attempted murder. With the invasion documents in hand, d'Éon held the king in check. D'Éon did not defend himself when Guerchy sued for libel, and he was declared an outlaw and went into hiding. However, d'Éon but secured the sympathy of the British public: the mob jeered Guerchy in public, and threw stones at his residence. D'Éon busied himself writing a long book on public administration, Les loisirs du Chevalier d'Éon, which was which published in thirteen volumes in Amsterdam in 1774.
Guerchy was recalled to France, and in July 1766 Louis XV granted d'Éon a pension for his services (or as a pay-off for silence) and gave him a 12,000-livre annuity, but refused a demand for over 100,000 livres to clear d'Éon's extensive debts. D'Éon continued to work as a spy, but lived in political exile in London. His possession of the king's secret letters protected him against further actions, but d'Éon could not return to France.
Life as a woman 
Despite d'Éon habitually wearing a dragoon's uniform, there were rumours that he was actually a woman, and a betting pool was started on the London Stock Exchange about his true sex. D'Éon was invited to join, but declined, saying that an examination would be dishonouring, whatever the result. After a year without progress, the wager was abandoned. In 1774, after the death of Louis XV, the secret du roi was abolished, and d'Éon tried to negotiate a return from exile. The French government's side of the negotiations was handled by the writer Pierre de Beaumarchais. The resulting twenty-page treaty permitted d'Éon to return to France and keep his ministerial pension, but required that d'Éon turn over the correspondence regarding the secret du roi.
The Chevalier d'Éon claimed to be physically not a man, but a woman, and demanded recognition by the government as such. He claimed to have been born anatomically female, but to have been raised as a boy because Louis d'Éon de Beaumont could only inherit from his in-laws if he had a son. King Louis XVI and his court complied, but demanded that d'Éon dress appropriately and wear women's clothing, although he was allowed to continue to wear the insignia of the Order of Saint-Louis. He agreed, especially when the king granted the chevalière funds for a new wardrobe. In 1777, after fourteen months of negotiation, d'Éon returned to France, and was banished to Tonnerre for six years.
He was allowed to return to England in 1785. The pension which had been granted by Louis XV was lost because of the French Revolution necessitating the sale of d'Éon's personal library, jewellery and plate. The family's properties in Tonnerre were confiscated by the revolutionary government. In 1792, he sent a letter to the French National Assembly, offering to lead a division of women soldiers against the Habsburgs, but the offer was rebuffed. D'Éon participated in fencing tournaments until being seriously wounded in in Southampton in 1796. His last years were spent with a widow, Mrs. Cole. In 1804 d'Éon was sent to a debtors' prison for five months, and signed a contract for an biography to be written by Thomas William Plummer. The book was never published, because d'Éon became paralyzed following a fall. His final four years were spent bedridden, and on 21 May 1810 he died in poverty in London at the age of 82.
Doctors who examined the body after death discovered that the Chevalier was anatomically male. He was buried in the churchyard of St Pancras Old Church. His remaining possessions were sold by Christie's in 1813.
- The term eonism was coined by Havelock Ellis to describe similar cases of transgender behavior; it is rarely used now.
- The Beaumont Society, a long standing society for transgendered people, is named after the Chevalier.
- The film Le secret du Chevalier d'Éon is loosely based on his life, but it portrays him as a woman masquerading as a man.
- Le Chevallier D'eon - a series of manga written by Tou Ubukata and illustrated by Kiriko Yumeji. It is published by Del Rey Manga
- Le Chevalier d'Eon - 2006 anime series loosely based on the Chevalier d'Éon.
- Eonnagata, a 2010 theatre piece by Canadian Robert Lepage, combining drama and dance, based on the life of Chevalier d'Éon.
- Some of d'Éon's papers are at the Brotherton Library in Leeds, U.K.
- In 2012, a painting owned by the Philip Mould Gallery was identified as being a portrait of d'Éon.
- J. M. J. Rogister, ‘D'Éon de Beaumont, Charles Geneviève Louis Auguste André Timothée, Chevalier D'Éon in the French nobility (1728–1810)’, Oxford Dictionary of National Biography, Oxford University Press, 2004; online edn, Sept 2012 accessed 26 April 2013
- Lever, Evelyne; Maurice Lever (19 February 2009). Le Chevalier d'Éon : Une vie sans queue ni tête. Fayard. pp. 384 pages. ISBN 978-2-213-61630-8.
- Burrows, Simon; Russell Goulbourne, Jonathan Conlin, and Valerie Mainz (23 April 2010). The Chevalier d'Éon and his worlds: gender, espionage and politics in the eighteenth century. Continuum. pp. 272 pages.
- Lettres, mémoires et négociations particulières du Chevalier D'Éon, ministre plénipotentiaire auprès du roi de Grande-Bretagne; avec M.M. les Ducs de Praslin, de Nivernois, de Sainte-Foy, & Regnier de Guerchy, Ambassad. Extr. &c.&c.&c. (1765)
- Burrows, Simon (October 2006). Blackmail, scandal and revolution London's French libellistes, 1758–92. Manchester, UK: Manchester University Press. 9780719065262.
- Laughton, John Knox, Dictionary of National Biography, 1885-1900, Volume 14 - D’Éon de Beaumont, Charles Geneviève Louis Auguste André Timothée
- Bryner, Jeanna (19 April 2012). "Earliest Painting of Transvestite Uncovered". Live Science. Retrieved 20 April 2012.
Further reading 
- Decker, Michel de. Madame Le Chevalier d'Éon. Paris: Perrin, 1987. ISBN 978-2-7242-3612-5.
- d'Éon De Beaumont, Charles. The Maiden of Tonnerre: The Vicissitudes of the Chevalier and the Chevalière d'Éon. Baltimore, MD: Johns Hopkins University Press, 2001. ISBN 978-0-8018-6687-6.
- d'Éon, Leonard J. "The Cavalier." New York, NY: G.P. Putnam's Sons, 1987. ISBN 0-399-13227-9.
- Frank, André, with Jean Chaumely. D'Éon chevalier et chevalière: sa confession inédite. Paris: Amiot-Dumont, 1953.
- Fortelle M. de la. La Vie militaire, politique et privée de Demoiselle Charles-Geneviève-Auguste-Andrée-Thimothée Éon ou d'Èon de Beaumont, [... etc.]. Paris: Lambert, 1779.
- Gaillardet, F. (ed.), Mémoires du chevalier d’Éon. Paris, 1836. 2 vols.
- Gontier, Fernande. Homme ou femme? La confusion des sexes. Paris: Perrin, 2006. Chapter 6. ISBN 978-2262024918.
- Homberg, O., and F. Jousselin, Un Aventurier au XVIIIe siècle: Le Chevalier D'Éon (1728-1810). Paris: Plon-Nourrit, 1904.
- Kates, Gary. Monsieur d'Éon Is a Woman: A Tale of Political Intrigue and Sexual Masquerade Baltimore, MD: Johns Hopkins University Press, 2001. ISBN 978-0-8018-6731-6.
- Lever, Évelyne and Maurice. Le Chevalier d'Éon: Une vie sans queue ni tête. Paris: Fayard, 2009. ISBN 978-2-213-61630-8.
- Luyt, Philippe. D'Éon de Tonnerre. Iconographie et histoire. 2007. OCLC 163617123
- Mourousy, Paul. Le Chevalier d'Éon: un travesti malgré lui. Paris: Le Rocher, 1998. ISBN 978-2-268-02917-7.
- Musée municipal de Tonnerre, Catalogue bilingue de l'exposition. Le Chevalier d'Éon: secrets et lumières, 2007. www.tonnerre.fr
- Royer, Jean-Michel. Le Double Je, ou les Mémoires du chevalier d'Éon. Paris: Grasset & Fasquelle, 1986. ISBN 978-2-246-38001-6.
- Telfer, John Buchan, "The strange career of the Chevalier d'Eon de Beaumont, minister plenipotentiary from France to Great Britain in 1763", 1885, OCLC 2745013
|Wikimedia Commons has media related to: Chevalier d'Éon|
- British Museum, Le Chevalier d'Eon, 1764, portrait
- British Museum, Mademoiselle La Chevaliere D'Eon de Beaumont, portrait
- British Museum, George Dance, Chevalier D'Eon, Graphite with watercolour, bodycolour and red stump, England, 1793, portrait and biography.
- British Museum, Chevalière d'Eon, satire
- British Museum, Additional holdings
- An article on the life of the Chevalier d'Éon
- An account by the Beaumont Society
- The Character of Chevalier d'Éon
- National Portrait Gallery: Portrait by Thomas Stewart, The Chevalier d’Eon
- The Strange Case of the Chevalier d’Eon, History Today Volume 60, Issue 4, 2010
- Portrait mistaken for 18th-century lady is early painting of transvestite, The Guardian, 6 June 2012