The Secret Plot to Rescue Napoleon by Submarine

In 1820, one of Britain’s most notorious criminals hatched a plan to rescue the emperor from exile on the Atlantic isle of St Helena — but did he try it?

Tom Johnson, the famous smuggler, adventurer, and inventor of submarines, sketched in 1834 for the publication of Scenes and Stories by a Clergyman in Debt.

Tom Johnson was one of those extraordinary characters that history throws up in times of crisis. Born in 1772 to Irish parents, he made the most of the opportunities that presented themselves and was earning his own living as a smuggler by the age of 12. At least twice, he made remarkable escapes from prison. When the Napoleonic Wars broke out, his well-deserved reputation for extreme daring saw him hired–despite his by then extensive criminal record–to pilot a pair of covert British naval expeditions.

But Johnson also has a stranger claim to fame, one that has gone unmentioned in all but the most obscure of histories. In 1820–or so he claimed–he was offered the sum of £40,000 to rescue the emperor Napoleon from bleak exile on the island of St. Helena. This escape was to be effected in an incredible way–down a sheer cliff, using a bosun’s chair, to a pair of primitive submarines waiting off shore. Johnson had to design the submarines himself, since his plot was hatched decades before the invention of the first practical underwater craft.

The tale begins with the emperor himself. As the inheritor of the French Revolution–the outstanding event of the age, and the one that, more than any other, caused rich and privileged elites to sleep uneasy in their beds–the Corsican became the terror of half of Europe; as an unmatched military genius, the invader of Russia, conqueror of Italy, Germany and Spain, and architect of the Continental System, he was also (in British eyes at least) the greatest monster of his day. In the English nursery he was “Boney,” a bogeyman who hunted down naughty children and gobbled them up; in France he was a beacon of chauvinism. His legend was only burnished when, defeated, apparently conclusively, in 1814 by a grand coalition of all his enemies, he was imprisoned on the small Italian island of Elba–only to escape, return to France, and, in the campaign famously known as the Hundred Days, unite his whole nation behind him again. His final defeat, at Waterloo, left the British determined to take no further chances with him. Exile to St. Helena, a small island in the South Atlantic 1,200 miles from the nearest land, was intended to make further escape impossible.

The emperor Napoleon in exile on St. Helena–a depressing prison for a man who had once ruled over most of Europe.

Yet, while Napoleon lived (and he endured six increasingly morose years on St. Helena before finally succumbing to cancer–or, some say, to arsenic poisoning), there were always schemes to rescue him. Emilio Ocampo, who gives the best account of this collection of half-baked plots, writes that “Napoleon’s political ambition was not subdued by his captivity. And his determined followers never abandoned hopes of setting him free.” Nor did the Bonapartists lack money; Napoleon’s brother, Joseph, who was at one time the King of Spain, had escaped to the United States with a fortune estimated at 20 million francs. And the emperor’s popularity in the United States was such that–Ocampo says–the British squadron taking him into exile headed several hundred miles in the wrong direction to evade an American privateer, the True Blooded Yankee, which sailed under the flag of the revolutionary government of Buenos Aires and was determined to effect his rescue.

The greatest threat, indeed, did come from South America. Napoleonic France had been the only power to offer support when the continent sought independence from Spain, and a few patriots were willing to contemplate supporting an escape or, more ambitiously, an invasion of St. Helena. The prospect was attractive to Napoleon as well; if there was no realistic hope of returning to Europe, he could still dream of establishing a new empire in Mexico or Venezuela.

St. Helena made an almost perfect prison for Napoleon: isolated, surrounded by thousands of square miles of sea ruled over by the Royal Navy, nearly devoid of landing places, and ringed with natural defenses in the form of cliffs.

Safely landed on St. Helena, though, the emperor found himself in what was probably the most secure prison that could have been devised for him in 1815. The island is extremely isolated, almost entirely ringed with cliffs and devoid of secure anchorages; it has only a handful of possible landing places. These were guarded by a large garrison, totaling 2,800 men, armed with 500 cannon. Napoleon himself, meanwhile, was held at Longwood, a refurbished mansion with extensive grounds in the most remote and dismal portion of the interior.

Although the emperor was allowed to retain an entourage, and offered a good deal of freedom within the confines of Longwood’s estate, everything else on the island was strictly controlled by St. Helena’s stern and officious governor, Sir Hudson Lowe, whose career prospects were intimately bound up with the security of his famous captive. Longwood was strongly guarded; visitors were interrogated and searched, and the estate was barred to visitors during the hours of darkness. An entire Royal Navy squadron, consisting of 11 ships, patrolled constantly offshore.

So concerned were the British to scotch even the faintest possibility of escape that small garrisons were even established on Ascension Island and at Tristan da Cunha, 1,200 miles further out in the Atlantic, to forestall the unlikely possibility that these uninhabited volcanic pinpricks might be used as staging posts for a rescue. No single prisoner, probably, has ever been so closely guarded. “At such a distance and in such a place,” the prime minister, Lord Liverpool, reported with satisfaction to his cabinet, “all intrigue would be impossible.”

Longwood, in the damp center of the island, was the emperor’s home for the last six years of his life.

And yet–surprisingly, perhaps–the British were right to take extreme precautions. The marines sent to occupy Ascension discovered that a message had already been left on its main beach–it read: “May the Emperor Napoleon live forever!”–and Ocampo summarizes a remarkably long list of plots to liberate the emperor; they included efforts to arrange a rescue by fast yacht, newfangled steamboat and even by balloon.

Where exactly Tom Johnson fits into this murky picture is difficult to say. Although scarcely averse to publicity, Johnson has always dwelt in the margins between fact and fiction–the latter often of his own invention.  Reliable records of his life are largely absent (even his name is generally misspelled Johnston or Johnstone); the one biography of him is a farrago. The greatest literary figure of the day, the novelist Sir Walter Scott, was misled about Johnson’s career–writing, wrongly, that he had piloted Admiral Nelson’s flagship at the Battle of Copenhagen.

Yet there is evidence that Johnson built a submarine, and that he talked openly, after Napoleon’s death, about his plan to use it. The most complete version of events, in what purport to be the smuggler’s own words, can be found in an obscure memoir entitled Scenes and Stories of a Clergyman in Debt, which was published in 1835, during Johnson’s lifetime. The author claimed to have met the smuggler in debtor’s prison, where (irritated by Scott’s misstatements, he suggests) Johnson agreed to put his tale in his own words. The book contains memoirs of several dramatic episodes that chime well with contemporary accounts–a remarkable escape from Fleet Prison, for example. At the very least, the correspondences lend weight to the idea that the material in Scenes and Stories really was written by Johnson–though of course it does not prove that the plot was anything but a flight of fancy.

The book’s account begins abruptly, with a description of his submarines:

Robert Fulton’s submarine of 1806 was developed from plans paid for by the British, and was probably the inspiration for Johnson’s designs. The papers were lodged with the American consulate in London and eventually published in 1920. Image: Wikicommons

The Eagle was of burthen of a hundred and fourteen tons, eighty-four feet in length, and eighteen foot beam; propelled by two steam engines of 40 horsepower. The Etna–the smaller ship–was forty feet long, and ten feet beam; burthen, twenty-three tons. These two vessels were thirty well chosen seamen, with four engineers. They were also to take twenty torpedoes , a number equal to the destruction of twenty ships, ready for action in case of my meeting with any opposition from the ships of war on the station.

The narrative passes silently over the not inconsiderable difficulty of how such small vessels were to make the voyage south to St. Helena, and moves on to their appearance off the island–the Etna so close to the shore that it would need to be “well fortified with cork fenders” to prevent being dashed to pieces on the rocks. The plan then called for Johnson to land, carrying “a mechanical chair, capable of containing one person on the seat, and a standing foot-board at the back,” and equipped with the enormous quantity of 2,500 feet of “patent whale line.” Leaving this equipment on the rocks, the smuggler would scale the cliffs, sink an iron bolt and a block at the summit, and make his way inland to Longwood.

I should then obtain my introduction to his Imperial Majesty and explain my plan… I proposed that coachman should go into the house at a certain hour… and that His Majesty should be provided with a similar livery, as well as myself, the one in the character of a coachman and the other as groom…. We should then watch our opportunity to avoid the eye of the guard, who seldom looked out in the direction of highest point of the island, and upon our arriving at the spot where our blocks, &c., were deposited, I should make fast one end of my ball of twine to the ring, and heave the ball down to my confidential man…and then haul up the mechanical chair to the top. I should then place His Majesty in the chair, while I took my station at the back, and lowered away with a corresponding weight on the other side.

The escape would be completed at nightfall, Johnson wrote, with the emperor boarding the Etna and then transferring to the larger Eagle. The two submarines would then make sail–they were to be equipped, Johnson’s account notes, with collapsible masts as well as engines. “I calculated,” he finished, “that no hostile ship could impede our progress…as in the event of any attack I should haul our sails, and strike yards and masts (which would only occupy about 40 minutes), and then submerge. Under water we should await the approach of an enemy, and then, with the aid of the little Etna, attaching the torpedo to her bottom, effect her destruction in 15 minutes.”

Charles de Montholon, a French general who accompanied Napoleon into exile, mentioned a plot to rescue the emperor by submarine in his memoirs.

So much for Johnson’s story. It does have some support from other sources–the Marquis de Montholon, a French general who went into exile with Napoleon and published an account of his time on St. Helena years later, wrote of a group of French officers who planned to rescue Napoleon “with a submarine,” and mentions elsewhere that five or six thousand louis d’or were spent on the vessel: about £9,000 then, $1 million now. The sober Naval Chronicle–writing in 1833, before the publication of Scenes and Stories–also mentions Johnson in connection with a submarine plot, though this time the sum involved was £40,000 , payable “on the day his vessel was ready to proceed to sea.” And an even earlier source, the Historical Gallery of Criminal Portraitures (1823), adds the vital missing link that explains why Johnson felt himself competent to build a submarine: 15 years earlier, when the Napoleonic Wars were at their height, he had worked with the renowned Robert Fulton, an American engineer who had come to Britain to sell his own plans for an underwater boat.

It is Fulton’s appearance in the tale that gives this account a semblance of verisimilitude. A competent inventor, best remembered for developing the first practical steamboat, Fulton had spent years in France peddling designs for a submarine. He had persuaded Napoleon to let him build one small experimental craft, the Nautilus, in 1800, and it was tested with apparent success on the Seine. A few years later, Fulton designed a second, more advanced, vessel which–as his illustration shows–superficially resembled Johnson’s submarines. It is also a matter of record that, when the French failed to show any interest in this second boat, Fulton defected to Britain with the plans. In July 1804, he signed a contract with the prime minister, William Pitt, to develop his “system” of submarine warfare under terms and conditions that would have yielded him £100,000 in the event of success.

St. Helena, an island of only 46 square miles, made a secure prison for a dangerous prisoner–or did it?

What is much harder to establish is whether Fulton and Tom Johnson met; the association is hinted at in several places, but nothing survives to prove it. Johnson himself was probably the source of a statement that appears in the Historical Gallery to the effect that he encountered Fulton in Dover in 1804 and “worked himself so far into secrets, that, when the latter quitted England…Johnstone conceived himself able to take up his projects.” Even more worrying is the suggestion that the book at the heart of this inquiry–Scenes and Stories of a Clergyman in Debt–is not all that it appears to be; in 1835, a denunciation appeared in the satirical newspaper Figaro in London, alleging that its real author was FWN Bayley–a hack writer, not a churchman, though he certainly spent time in jail for unpaid debts. The same article contained the worrying statement that “the most extraordinary pains have been taken by the publisher to keep…Captain Johnson from sight of this work.” Why do that, if Johnson himself had penned the account that appeared under his name?

Might Johnson have been no more than a fantasist, then–or at best a man who touted extravagant claims in the hope of making money from them? The old smuggler spent the 1820s talking up a whole succession of projects involving submarines. At one point he was reported to be working for the king of Denmark; at another for the pasha of Egypt; at yet another to be building a submarine to salvage a ship off the Dutch island of Texel, or to retrieve valuables from wrecks in the Caribbean. Perhaps this is not surprising. We know that, after emerging from debtors’ prison, Johnson lived for years south of the Thames on a pension of £140 a year–a little less than $20,000 today. That was scarcely enough to allow life to be lived to its fullest.

Sir Hudson Lowe, Napoleon’s jailer on St. Helena, was responsible for the security precautions Johnson sought to evade.

Yet, oddly enough, the jigsaw puzzle that is Johnson’s life includes pieces that, properly assembled, hint at a much more complex picture. The most important of these scraps remain unpublished and molder in an obscure corner of Britain’s National Archives–where I unearthed them after a dusty search some years ago. Together, they give credence to an odd statement that first appeared in the Historical Gallery–one that dates the construction of Johnson’s submarine not to an 1820 approach by wealthy Bonapartists, but to as early as 1812, three years before Napoleon’s imprisonment.

What makes this detail especially interesting is the context. In 1812, Britain was at war with the United States–and the U.S. was known to have employed Robert Fulton to work on a new generation of super-weapons. That probably explains how Johnson was able to arm himself with a whole series of passes from different government departments confirming that he was formally employed “on His Majesty’s Secret Service on submarine, and other useful experiments, by Order.” How these trials were funded is a different matter. In the confusion of wartime, the papers show, Britain’s army and navy each assumed that the other would be picking up the bill. It was a situation Johnson was quick to exploit, retaining the services of a London engineer who sketched a submarine that was 27 feet long and “in shape much like a porpoise.” An inner chamber, six feet square and lined with cork, protected the two-man crew.

There is no doubt that Johnson’s design was primitive–the submarine was driven by sails on the surface, and relied on oars for motive power when submerged. Nor is there anything to suggest that Tom and his engineer solved the vast technical problems that prevented the development of effective subs before the 1890s–most obviously the difficulty of preventing a boat submerging in neutral buoyancy from simply plunging to the bottom and staying there. It was enough that the weapon actually existed.

The White House is burned down on the orders of Sir George Cockburn. In 1820, the British admiral would go on to write up a report on Tom Johnson’s submarine.

We know it did, because the archives contain correspondence from Johnson confirming that the boat was ready and demanding payment of £100,000 for it. They also show that, early in 1820, a commission of senior officers, led by Sir George Cockburn, was sent to report on the submarine–not, apparently, to assess its new technology, but to estimate how much it cost. Cockburn was a serious player in the naval hierarchy of the day, and remains notorious as the man who burned the White House to the ground when Washington fell to British troops in 1814. His original report has vanished, but its contents can be guessed from the Royal Navy’s decision to shave Johnson’s six-figure demand down to £4,735 and a few pennies.

What this means is that, early in 1820, Johnson possessed a very real submarine at precisely the time that, French sources suggest, Bonapartist officers were offering thousands of pounds for just such a vessel. And this discovery can be tied, in turn, to two other remarkable reports. The first, which appeared in the Naval Chronicle, describes a trial of Johnson’s boat on the River Thames:

On one occasion, the anchor… got foul of the ship’s cable…and, after having fixed the petard , Johnson strove in vain to get clear. He then looked quietly at his watch, and said to the man who accompanied him, “We have but two minutes and a half to live, unless we can get clear of this cable.” This man, who had been married only a few days, began to lament his fate…. “Cease your lamentations,” said Johnson sternly to him, “they will avail you nought.” And, seizing a hatchet, he cut the cable, and got clear off; when immediately the petard exploded, and blew up the vessel.

The second account, in the unpublished memoirs of the London artist Walter Greaves, is a recollection by Greaves’s father–a Thames boatman who recalled how “one dark night in November” , the smuggler was intercepted as he attempted to run his submarine out to sea. “Anyhow,” Greaves ended,

she managed to get below London Bridge, the officers boarding her, Capt. Johnson in the meantime threatening to shoot them. But they paid no attention to his threats, seized her, and, taking her to Blackwall, burned her.

Napoleon in death–a sketch by Denzil Ibbetson made on May 22, 1821. The emperor’s demise ended Johnson’s hopes of using a submarine paid for by the British government to free his country’s greatest enemy.

Taken together, then, these documents suggest that there is something in an old, tall story. There is no need to suppose that Napoleon himself had any inkling of a plan to rescue him; the scheme Johnson laid out in 1835 is so woolly it seems likely that he planned simply to try his luck. Such evidence as survives from the French side suggests that the emperor would have refused to go with his rescuer in the unlikely event that Johnson had actually appeared at Longwood; salvation in the form of an organized invasion was one thing, Bonaparte thought; subterfuge and deeds of desperate daring quite another. “From the start,” Ocampo says, Napoleon “made it very clear that he would not entertain any scheme that would require him to disguise himself or require any physical effort. He was very conscious of his own dignity and thought that being captured as a common criminal while escaping would be demeaning.… If he left St. Helena, he would do it ‘with his hat on his head and his sword at his side,’ as befitted his status.”

The mental picture remains a vivid one, nonetheless: Napoleon, squeezed uncomfortably into footman’s clothing, strapped to a bosun’s chair and dangling halfway down some vertiginous cliff. Behind him stands Tom Johnson, all but six foot in his socks, lowering rapidly away toward the rocks–while offshore lurk Etna and Eagle, sails furled, fearsomely armed, ready to dive.


John Abbott. Napoleon at St Helena. New York: Harper & Brothers, 1855; Anon, “On submarine navigation.” The Nautical Magazine, April 1833;  Anon . Scene and Stories by a Clergyman in Debt. London, 3 vols.: A.H. Baily & Co, 1835; John Brown. The Historical Gallery of Criminal Portraitures. Manchester, 2 vols: L. Gleave, 1823; James Cleugh. Captain Thomas Johnstone 1772-1839. London: Andrew Melrose, 1955; Mike Dash. British Submarine Policy 1853-1918. Unpublished PhD thesis, King’s College London, 1990; Figaro in London, March 28, 1835; Huntingdon, Bedford & Peterborough Gazette, February 1, 1834; Emilio Ocampo. The Emperor’s Last Campaign: A Napoleonic Empire in America. Apaloosa: University of Alabama Press, 2009; Emilio Ocampo. “The attempt to rescue Napoleon with a submarine: fact or fiction?Napoleonica: La Revue 2 (2011); Cyrus Redding. Fifty Years’ Recollections, Literary and Personal, with Observations on Men and Things. London, 3 vols.: Charles J. Skeet, 1858.

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