What killed Napoleon Bonaparte?

The day after his death in British custody on 5 May 1821, 16 observers attended the autopsy, seven doctors among them. They were unanimous in their conclusion: Napoleon had died of stomach cancer.

Nevertheless, the doubts Napoleon had fomented about what ‘really’ happened have never quite gone away: did the British government hasten his death? Did French rivals slip poison into his wine? Was it even Napoleon who died in Longwood House in May 1821? For nearly two centuries, all these questions and more have been discussed, disputed and recycled.

Born to a Corsican family of modest means in 1769, by 1811 Napoleon Bonaparte ruled 70 million people and dominated Europe. Four years later, his dynastic, political, imperial and military dreams were shattered and he was exiled to St Helena, a remote island in the South Atlantic, under British guard. There, until his death he and his cooped-up, fretful household lived in a rambling villa called Longwood House.

A slow death

That death did not come suddenly. For months Napoleon suffered from abdominal pain, nausea, night sweats and fever. When he was not constipated he was assailed by diarrhea; he lost weight. He complained of headaches, weak legs and discomfort in bright light.

His speech became slurred. The night sweats left him drenched. His gums, lips and nails were colourless. Briefly, he got it into his head that he was being poisoned, but then he decided he had the same cancer that had killed his father, and that all medical help was useless. On 4 May 1821, he lost consciousness. On 5 May, news went out to a shocked world that the great man was dead – and the questions began.

The first conspiracy theorist was the Irish doctor Barry O’Meara, who had been ship’s surgeon on HMS Bellerophon when Napoleon surrendered to her captain after the battle of Waterloo, and became Napoleon’s personal physician. O’Meara tended the ex-emperor for three years, until he made the bombshell claim that the British governor of St Helena, Sir Hudson Lowe, had commanded him to “shorten Napoleon’s life”. He was, unsurprisingly, sacked.

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Sir Hudson was eminently well-cast as a sneering British villain, which is the version that has come down through history and, not by coincidence, the version that Napoleon wanted the world to believe. Napoleon had a cunning plan to escape St Helena by claiming its unhealthy climate was fatally weakening him, and using Dr O’Meara’s medical authority in support.

O’Meara fell for his patient’s famous charm and obediently backed up his claims: in 1818, he accused Governor Lowe of attempting to hasten Napoleon’s death, and in 1822, he published a book claiming the British government had been determined to eliminate all possibility of another Napoleonic comeback.

Many people suspected O’Meara was right, but nobody could prove it. No method yet existed to prove the presence of arsenic in a corpse, and Napoleon’s was, in any case, buried in four coffins and under a large slab of rock. If Napoleon had been murdered, it looked as if the killer had got away with it – until, that was, a pipe-smoking Swedish dentist came across the story some 100 years later and took up where O’Meara had left off.

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Was Napoleon murdered?

When the private papers of Napoleon’s valet de chambre were published in the 1950s, offering intimate accounts of the emperor’s final days, Dr Sten Forshufvud believed he had spotted a smoking gun.

Of 31 symptoms of arsenic poisoning discovered by scientists since 1821, Napoleon presented 28, so Forshufvud asked a Scottish university to conduct a newly-invented arsenic-detection test. Neutron activation analysis (NAA) was carried out on hairs from Napoleon’s head dated to 1816, 1817 and 1818 – he was a prodigious gifter of locks – and revealed fatally high levels of arsenic in his system. O’Meara, it seemed, had been right: Napoleon had been murdered – but by whom?

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Canadian bodybuilding millionaire Ben Weider (discoverer of the young Arnold Schwarzenegger) was arriving at the same conclusion by means of a different method. Convinced that Napoleon had been ‘done in’, Weider had combed the many memoirs written by members of the Longwood household for clues.

When he and Dr Forshufvud collated evidence of the symptoms described in the memoirs and compared them with the peaks and troughs of arsenic absorption displayed by the NAA analysis, they believed they had evidence of doses administered at intervals over several years. Their uncompromisingly-titled book Assassination at St Helena also named a new suspect: Napoleon’s old companion Charles Tristan, marquis de Montholon, a shady character whose wife Napoleon had seduced, who was desperate to get off the island and who stood to gain personally from the will.

The restored Bourbon kings of France (who had as much interest as the British in keeping Napoleon down) had (they claimed) threatened to make Montholon’s embezzlement of military funds public if he did not agree to slip Napoleon an arsenical Mickey Finn [a laced drink].

Was Napoleon poisoned with arsenic?

This colourful theory did not convince everyone, however: even if arsenic had killed Napoleon, this did not mean someone had killed Napoleon with arsenic. In the 1980s the poisoning debate veered in a different direction, theorising that Napoleon could simply have absorbed enough arsenic from his environment to kill him off. A 19th-century house was saturated in arsenic: cosmetics, hair tonic, cigarettes, sealing wax, cooking pots, insect-repellent powders, rat poison, cake icing – all were toxic.

When a Newcastle University chemist experimented on a scrap of Longwood wallpaper stolen by a 19th-century tourist, he discovered poisonous gases exhaled by a mould growing behind it could even have contributed to napoleon’s fatal decline. Later researchers tested hairs from Napoleon’s son; his first wife, the Empress Josephine; and 10 living persons, and concluded that Europeans in the early 19th century had up to 100 times more arsenic in their bodies than the average person living now. Inanimate guilty parties suddenly swarmed the crime scene.

The ‘murder school’ was having none of it. For several years, the two schools of thought slugged it out with tests and counter-tests: the FBI, Scotland Yard, the Strasbourg Forensic Institute, the laboratories of the Paris police – all carried out tests, and all confirmed that high levels of arsenic had been present in Napoleon’s system, but still no one could definitely answer the question of how the poison had got there.

Is Napoleon's tomb empty?

Meanwhile, a second debate rumbled away in the background: substitution. The idea of the substitute emperor has been used in films and novels and certainly, Napoleon’s more besotted admirers were (and are) sure that he lived on – and that the man who died on 5 May was someone else.

The most startling version of the substitution theories claims that Napoleon never went to St Helena at all: that a double was dispatched in his place while the ex-emperor retired to Verona and peaceably sold spectacles, until he was shot attempting to scale the walls of an Austrian palace to see his young son. Sadly, the tale has no documentary basis whatsoever.

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A second substitution theory revolves around Jean-Baptiste Cipriani, butler at Longwood until his death in February 1818 during a hepatitis epidemic, and buried nearby. The ‘Cipriani school’ claims that the British secretly dug up Napoleon’s body in the late 1820s for inexplicable reasons of their own.

When faced with a French request in 1840 to disinter Napoleon and bring him back to Paris, the British therefore hurriedly dug Cipriani up and dropped him into Napoleon’s empty tomb. Why, the ‘Cipriani school’ has demanded, did the British officer in charge allow the French observers present to see the body only at midnight, by torchlight? Why would he not allow sketches to be made? Why was the coffin only opened for two minutes before it was shut up again and taken aboard the French frigate?

Fake death masks, rotting socks, disappearing facial scars, the position of viscera-holding vases – the details claimed and denied are too many to go into here, but kept Napoleonic studies happy for years. In 1969, the bicentenary of Napoleon’s birth, a French journalist even published a deliberately sensational ‘appeal’ to the British: Anglais, rendez-nous Napoleon! (Give us back Napoleon!) His startling contention was that the British royal family had had Napoleon reburied in Westminster Abbey, the ultimate insult.

The more prosaic truth is that Napoleon’s body (almost) certainly lies under the dome of Les Invalides in Paris. However, until French authorities allow the coffin to be opened for tests, theories will continue to swirl – some in respectable books and some in the more excitable corners of the internet – about the ultimate fate of one of history’s most fascinating characters.

Siân Rees is author of The Many Deaths of Napoleon Bonaparte

This content was first published by HistoryExtra in July 2016