The Poison In Napoleon's Wallpaper

On 5 May 1821, Napoleon Bonaparte — the man who had once ruled most of Europe — died in a damp, mould-streaked house on the tiny, remote island of St. Helena, where the British had exiled him after his final defeat at Waterloo. He was 51 years old.

The official cause of death, determined by autopsy the following day, was advanced stomach cancer. His father had also died of a stomach illness believed by some to have been cancer. It should have been the end of the story. Instead, it became one of history’s longest-running forensic mysteries.

Because Napoleon did not believe he was dying naturally. Just three weeks before his death, he wrote a chilling line into his will: “I die before my time, murdered by the English oligarchy and its assassin.” The fallen emperor believed his enemies had killed him. For a long time, evidence appeared to support that fear.

The Horror

The mystery caught fire thanks to a peculiar custom. After Napoleon died, locks of his hair were snipped from his head as keepsakes and scattered into private collections and museums. More than a century later, as forensic science advanced, preserved locks attributed to Napoleon were tested.

The results were startling. Some samples contained arsenic at levels far above modern norms. Arsenic was the classic poison of the era: difficult to detect, capable of causing serious illness, and associated with slow poisoning theories. Suddenly, Napoleon’s dying accusation looked horribly plausible.

And there was another eerie detail. In 1840, nearly twenty years after his death, Napoleon’s remains were exhumed from St. Helena and returned to France for reburial in Paris. Witnesses described his body as remarkably well-preserved. Poisoning theorists seized on this, arguing that arsenic could slow decomposition and help preserve a corpse.

So who did it? The poisoning theory found a prime suspect close to home: Count Charles de Montholon, a member of Napoleon’s inner circle who lived with him at Longwood House throughout the exile. Montholon had opportunity. He was close to Napoleon, had access to his household and later received a substantial bequest in Napoleon’s will. His wife, Albine, was also rumoured to have been Napoleon’s mistress.

The theory, championed for decades by determined researchers, was that Montholon had slowly poisoned Napoleon — perhaps for his own gain, perhaps on behalf of the British, who had every reason to fear another escape after Napoleon’s return from Elba in 1815. It was a gripping tale of intrigue and assassination. But it has never been proven.

The Modern Relic

Then science began to complicate the story. In the 1980s, British scientist Dr David Jones proposed an alternative theory involving the walls of Longwood House. The wallpaper was green, and green pigments of the era often contained arsenic. In the chronically damp conditions at Longwood, Jones suggested that mould might have converted arsenic in the wallpaper into an airborne compound.

It was a fascinating idea. Other people at Longwood complained of poor health and bad air, while surviving samples of wallpaper were found to contain arsenic. Perhaps Napoleon had not been murdered by a traitor at all, but exposed to arsenic in his own prison house.

But the wallpaper theory, too, remains unproven. The wallpaper contained arsenic, but historians and scientists disagree on whether it released enough arsenic to seriously poison Napoleon. It may have contributed to his background exposure, but there is no strong evidence that it killed him.

Then came the most important twist. Researchers tested hair attributed to Napoleon from different points in his life — not just from his deathbed, but from years before St. Helena, including childhood and his earlier career. The tests found that his arsenic levels were often elevated throughout his life, long before any alleged poisoner at Longwood could have reached him.

Researchers also found high arsenic in hair attributed to members of Napoleon’s family and people from his era. Arsenic exposure in the early nineteenth century could come from medicines, dyes, paints, food, wine, cosmetics and other everyday materials. The presence of arsenic in Napoleon’s hair, by itself, could not prove murder.

That did not mean the hair evidence was meaningless. Some researchers have continued to argue that the levels were unusually high and could indicate chronic poisoning. But the fact that levels varied between samples — including samples supposedly cut at similar times — made hair evidence difficult to interpret with certainty.

And so, after all the drama, modern medical analysis has largely returned to the original diagnosis. In 2007 and again in 2021, researchers who re-examined Napoleon’s symptoms and the detailed descriptions from the autopsy concluded that he most likely died of advanced gastric cancer, probably with internal bleeding and complications in his final days.

The autopsy described much of Napoleon’s stomach lining as cancerous, with signs of severe disease and bleeding. That physical evidence matches his prolonged decline: stomach pain, nausea, vomiting, weakness, loss of appetite and wasting.

So the great murder mystery of Napoleon Bonaparte ends not with a poisoner’s confession, but with a quieter and more human truth. A dying, defeated emperor, isolated on a windswept rock in the middle of the ocean, believed his enemies were killing him. But the best available evidence indicates that he was dying from advanced stomach cancer — perhaps worsened by the harsh conditions, treatments and environmental exposures of his age.

The English almost certainly did not murder Napoleon. But the accusation he wrote into his will kept the world guessing for two hundred years — a final, unintended mystery from a man who never could bear to lose.

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