**Jakob Leonhard was officially a Nazi spy. Unofficially, he worked for Switzerland. Illustration by Marco Heer.**

Double agent Leo

Jakob Leonhard spied for the Nazis. When they realised that the information he was feeding them had been rubber-stamped by Switzerland, his life hung by a thread.

Gabriel Heim

Gabriel Heim is a book and film author and exhibition organiser. He is principally concerned with research into topics of modern and contemporary history and lives in Basel.

The seven-month prison sentence Jakob Leonhard had to serve at Horgen district prison (ZH) for his unauthorised military service in the Spanish Popular Front appears to have brought him neither peace nor insight. It must have preyed on his mind, because in his memoirs he notes: ‘I was itching to show that a “Spanienfahrer” (a person who volunteered to fight in Spain) need not be a bad Swiss citizen – on the contrary!’ But how was he to go about proving that, now that he had been barred from the army following the outbreak of the Second World War? Leonhard seemed prepared to grasp any opportunity that presented itself, even if it was just another adventure with an uncertain outcome.

In 1941, his chance finally came. ‘Handsome Emil’, an old workmate who had moved to Germany and had since made a career there as a staunch Nazi, got in touch with him – under mysterious circumstances. Emil Lang had a secret mission. He was looking to recruit agents to beef up Germany’s spy network in Switzerland. Slighted by his homeland and lacking any real direction, Leonhard seemed to Emil a likely candidate. And so, in a cosy summer evening chat over free-flowing wine and schnapps, the two men came to an agreement, despite Leonhard’s initial reservations about committing treason. Soon after, Leonhard had an exit visa issued by the German consulate in Zurich and 500 francs in his hands.

Entry to the SS

In early December 1941, his ‘pact with the devil’ took Leonhard to Strasbourg, where he was expected at the luxurious Graf Zeppelin hotel and supplied with ‘a large quantity of money and food ration cards’. From there his journey, in the company of a certain Dr Martin – his handler – continued to Stuttgart. According to Leonhard, he negotiated the terms of his engagement with another German official there. They agreed on his activities, remuneration and entry to the SS. ‘I was thus under German military law. My entry to the SS could have no other meaning.’ Equipped with orders and Basel cover addresses, Jakob Leonhard set off on the return journey to Switzerland.

On 2 March 1942, Leonhard reported to the Swiss authorities. He told Captain Gyr of Zurich Territorial Command that he had already been recruited and paid by the German intelligence service. Gyr referred him to the political division of Zurich city police, where Detective Sergeant Bleiker became his main contact. From then on, Leonhard continued working for the German intelligence service with the knowledge of the Swiss authorities, while supplying his Swiss contacts with information about its activities. The man from Zurich was now a double agent. ‘I felt happier and more cheerful than I had for a long time. It had not been easy having to stand on the sidelines all these years, while Switzerland was in danger. Now, once again, I had a duty to carry out a perilous but crucially important task.’

From then on, Leonhard trod a careful line between his Swiss contacts and his German assignments, which he initially handled via a dead drop and soon also through his go-between, Emil Bernauer – a German railway employee based at Basel’s Badischer Bahnhof. In Stuttgart his work was highly regarded, and people had no idea that the military secrets passed on by the Swiss agent were rubber-stamped in Zurich. His assignment also included tailing German spies belonging to other intelligence networks operating in Switzerland. Leonhard was convinced that he had quickly seen through the entire agent network. He found ways and means to discreetly keep his covert Swiss contacts up to date. It was a delicate balancing act – in the system of mutual distrust among the German agents, he had to be prepared to be exposed himself at any moment.

From then on, Leonhard trod a careful line between his Swiss handler and the orders that he was required to pass on, initially via a dead drop, and soon also through his go-between, Emil Bernauer – a German railways employee based at Basel’s Badischer Bahnhof. In Stuttgart his work was highly regarded, and people had no idea that the military secrets passed on by agent Leo were rubber-stamped in Zurich. His assignment also included tailing the German spies who were in other Swiss lines in Switzerland. The clever Leo quickly had his tentacles into every corner of the agent network. He found ways and means to discreetly keep his covert Swiss side up to date. It was a delicate balancing act – in the system of mutual distrust among the German agents, he had to be prepared to be ‘hung out to dry’ himself at any moment.

**The spies’ rendezvous: the Badischer Bahnof in Basel.** Swiss National Museum

In September 1943, Emil Bernauer and his intelligence network – comprising agents, couriers and contacts – were arrested in Basel. Leonhard was summoned to Strasbourg by Dr Martin to report. He managed to refute an initial suspicion that he had betrayed Bernauer. But his loyalty was now suspect, and he remained in Switzerland for the next few months.

Leonhard is exposed

Eventually, however, another journey to the German Reich could no longer be postponed. Despite warnings from the Swiss authorities, Jakob Leonhard travelled to Strasbourg in April 1944. The trip proved to be his undoing.

As usual, his arrival was celebrated in the ‘inner circle of the Gestapo with wine and oysters from Paris’. ‘But in the middle of the night’ – he writes – ‘they set upon me like beasts. I was bleeding from my mouth and nose; my face was swollen and misshapen. I couldn’t move a limb.’ Leonhard was dragged off to the Gestapo in Strasbourg. ‘You are charged with betraying us. We have unaccountably lost our best people in Switzerland – and you are still on the loose. How do you explain that?’ Then, recalls the double agent, ‘four SS men, strapping, brutal lads in riding breeches and heavy boots, came into the room. I was driven to Kehl at breakneck speed. The official welcome took place in cell 29. When the prison guard heard that I was Swiss, he laid into me with a roar: Filthy Swiss scum! Jew dog! Goddamned communist crook!’

The ordeal was never-ending. ‘An honest-to-God gorilla with huge hairy paws, the like of which I’d never seen in my life, set about pummelling me with his feet and fists. You won’t be the first foreigner we’ve beaten to death here, just as you deserve!’ In the days that followed, Leonhard was repeatedly hauled in for questioning. ‘My face and body were swollen. I was racked by excruciating pain. My undergarments were a single red rag after this procedure.’

**Picture of Jakob Leonhard shortly after his return to Switzerland, 1945.** by courtesy

Sentenced to death by beheading

On 22 August 1944, Leonhard was brought before the judges of the People's Court in Zweibrücken. After a brief trial, during which his ‘defence counsel’ remained silent, he was sentenced to death for treason, to be carried out by beheading with an axe. But the sentence was never executed. On the one hand, Leonhard tried to buy some time by slashing his wrists on two occasions. On the other, the Swiss authorities had contacted the German Reich's Foreign Office in October to request a postponement of the execution. The request was granted in view of a possible prisoner exchange.

**In August 1944, the trial of ‘travelling salesman’ Jakob Leonhard took place in Zweibrücken.** Swiss Federal Archives

For months, Jakob Leonhard languished in German prison cells. After his suicide attempts, he was put in a straitjacket ‘for his own safety’. ‘In the cell, my hands and feet were tied to rings set into the floor, so that I was sitting there like a fakir in the middle of the room. The food I was given was a filthy wastewater broth. The guard just dumped it into my cell; I had to lick it up off the dirty, blood-encrusted floor… For a full week I had to relieve myself where I sat.’ Every day, Leonhard overheard other prisoners being ‘liquidated’ and expected to be executed himself. He was most probably unaware that Switzerland had secured a suspension of his death sentence.

In December 1944, the two countries agreed on a prisoner exchange: Jakob Leonhard was to be exchanged for Karl Heller. The German from the German enclave of Büsingen had been sentenced to ten years in prison for offences including the disclosure of military secrets and had been in custody since March 1942.

**German letter to the Swiss Legation, November 1944.** Swiss Federal Archives

**Swiss proposal from December 1944 for a prisoner exchange involving Jakob Leonhard and Karl Heller.** Swiss Federal Archives

It would be several more weeks before the double agent could return to Switzerland. It was not until early March that the Swiss national was transferred to Bregenz, where Carl Bitz, the Swiss consul in Bregenz, greeted him in Swiss German: ‘I believe you are Herr Leonhard.’ Bitz then drove Jakob Leonhard back to Switzerland. After almost a year, the man from Zurich was free again.

Money and fame after the war

Jakob Leonhard first published an account of his experiences as a newspaper article and then as a book entitled Als Gestapo-Agent im Dienste der Schweizer Gegenspionage (My life as a Gestapo agent in the service of Swiss counter-espionage). In the immediate post-war period there was enormous interest in real-life stories from Germany, and the book was a bestseller. His honour was also restored when the Federal Council reversed his military demotion.

**In 1945 Jakob Leonhard published a book of his memoirs from his time as a spy.** by courtesy

Six months later, the General Staff authorised the payment to him of ‘compensation of 6,000 Swiss francs for his imprisonment in Germany’. Without the help of secret diplomacy, Jakob Leonhard would have paid with his life for his game of va banque. The fact that he still refused to settle down, wrangling with Switzerland for years over a higher level of compensation, suggests that even in peacetime, ‘Agent Leo’ lived a double life, which is only possible if you have more than one truth.

**The Eidgenössische Militärdepartement (Federal Military Department) recommended to the Federal Council that compensation be paid.** Swiss Federal Archives

Postscript: Leonhard’s go-between at the Badischer Bahnhof, the German Emil Bernauer, was sentenced to 20 years in prison with subsequent expulsion from the country. His ‘most diligent informant’, a Swiss man called Samuel Plüss, was brought before a military court and sentenced to death by firing squad for treason. The sentence was carried out on 13 December 1944 in Allschwil (BL).

By the way, Jakob Leonhard was betrayed by Bernauer’s wife, Alma. In 1943 she went to the Gestapo in Strasbourg and denounced him in revenge for allegedly informing on her husband. In 1945, Alma Bernauer was sentenced in Basel to one year in prison and 12 years’ expulsion from the country.

Before embarking on his ‘career’ as a double agent, Jakob Leonhard was a fraud and a trickster. He passed himself off as an anti-fascist fighter and claimed to have fought on the frontlines in the Spanish Civil War. For that he was jailed in Switzerland. Read the first part of the story here.

More of: 20th / 21st century Politics War/battle Article

Further posts

When bombs fell on Kallnach

Juri Jaquemet 06.01.2023 On 6 January 1918, five bombs were dropped near the station in Kallnach, sending shock waves through the ‘Grand Marais’ in Bern’s Seeland region. Fortunately, there was only some damage to property but no casualties. It quickly became clear that the bombs were French-made. But the question of who dropped them remains a mystery...

In early January 1918, the Bernese village of Kallnach was bombed. This postcard from 1915 shows the station close to where the bombs exploded.

The forgotten war hero

Thomas Weibel 04.05.2022 Discovered in a museum storeroom, a magnificent portrait of a horseman proves to be witness to a life straight out of an adventure novel: Fribourg mercenary leader Franz Peter König’s wild gallop through the Thirty Years’ War.

Allow me to introduce myself: Leonhard, war hero…

Andrej Abplanalp 12.08.2021 Jakob Leonhard fought against the fascists in the Spanish Civil War. Or did he? The strange story of a Zurich taxi driver who slipped away mysteriously, only to return a hero.