Unlike many others in the area, the beach on the coast of Sao Paulo in Brazil was good for swimming.
Wolfram and Liselotte Bossert, an Austrian couple who had moved to South America, went into the water one summer afternoon in 1979 with the family friend they called ‘Uncle Peter’.
Peter was a good swimmer but that day he raised his arm, asking for help. He seemed to be drowning. Rescuers managed to drag him out but he was already dead.
Lifeguards summoned the police, who found Liselotte nervous. She told them that the dead man was her uncle. Asked for his documents, she handed over his ID card, which stated his name as Wolfgang Gerhard, born in Austria on September 3, 1925.
Despite the paperwork being for a 53-year-old man and the deceased being aged 67, the police didn’t notice. To them, it was just a typical accident.
For Liselotte, sadness apart, many practical issues were at stake; she knew the body was that of Josef Mengele, one of the world’s most wanted war criminals.
Would she now reveal the identity of the man she had helped to hide for ten years?
Her first decision was to stick to the version that the dead man was indeed Wolfgang Gerhard, as stated on the ID card. Apart from the photograph, which was of Mengele, it bore the authentic details of this Austrian friend who had introduced him to the Bossert family.
Josef Mengele with Liselotte Bossert and her children Sabine, left, and Andreas in Brazil, 1982
Jewish children at Auschwitz, where Mengele, known as the ‘Angel of Death’ carried out numerous medical experiments on prisoners, especially twins
Mengele, centre, with the commandment of Auschwitz Richard Baer, left, and Rudolf Hoss
There was no autopsy and Liselotte asked the funeral assistant to leave the deceased’s arms alongside the body, rather than crossed at his chest – a request that Mengele himself had made to her, for, as a soldier, he should be laid to rest standing at attention.
Once the burial was over, Liselotte went home and believed the secret she had kept for so long was now buried – literally.
She was sure she was doing the right thing. A Catholic, she believed that God would help her because her only crime had been to help a friend whom she considered to be a scientist, and not a degenerate doctor who sent thousands to die in the gas chambers of Auschwitz.
It was only as an adult that I discovered that Liselotte, who had been my childhood teacher, had protected the world’s most wanted Nazi criminal. Her deception had foiled the authorities, Nazi hunters and Mengele’s surviving victims who were seeking justice.
As a journalist, I decided to get to the bottom of this story.
Mengele’s cruel and bizarre experiments had always haunted me. His job was to select which prisoners should die in the gas chambers and which could be put to work. Nicknamed the ‘Angel of Death’, he used twins and people with dwarfism or other rare conditions as human guinea pigs in his vile experiments.
In Auschwitz, all pregnant women were sent to the gas chamber, but on one occasion Mengele spared two women to experiment on their newborns. He ordered a doctor to tie one mother’s breasts with a tight bandage so that she couldn’t nurse the infant, as he wanted to know how long a baby could survive without its mother’s milk. After seven days of agony and despair – and knowing that Mengele was to send her and the baby to the gas chamber the next day – a fellow prisoner gave the woman some morphine to fatally inject into her child.
I managed to find Liselotte, then aged 90, in Brazil. Slowly she began to open up to me and the remarkable story was revealed. For six years after Mengele drowned, she continued teaching but then, in June 1985, she suddenly found herself indicted for three crimes: hiding a fugitive, making a false statement in a public document, and using a false document.
After the Nazis were defeated in the Second World War, Mengele, like many prominent Nazis, fled to South America
An estimated 1.1 million prisoners were killed at Auschwitz, 960,000 of which were Jews
Her husband duly explained to police that Mengele had known he was being sought all over the world, but, using a network of loyal supporters, had created a ‘Tropical Bavaria’ in Brazil: where he could speak German and maintain his customs, beliefs, friends and connection to his homeland. Mengele’s whereabouts throughout that time was a global mystery that fuelled countless conspiracy theories.
The famous Nazi hunter Simon Wiesenthal was convinced the former SS captain was at a military base in Paraguay. It was alleged that the Americans had captured him shortly after the war and released him.
The fact that the US had recruited hundreds of Nazi scientists to work on military and space projects led to the suspicion that Washington sympathised with Third Reich fugitives. Over the years, there were numerous official attempts to locate Mengele, Israel’s secret intelligence service Mossad was put on the case several times and huge rewards were offered.
Liselotte could have cashed in, even with Mengele dead, but she remained silent. When the war ended in Europe, it wasn’t possible to arrest all eight million Nazis in Germany. With the evacuation of Auschwitz, Mengele ended up in a military hospital.
This could have been the end of the line for him as he was on a United Nations War Crimes list of wanted criminals but he started using false names.
While being screened by American soldiers, all German prisoners were checked to see whether they had a tattoo under their left arm given to all SS members notifying their blood type. Those who didn’t were released.
But SS officers who had joined before the war did not have this tattoo – and such was the case with Mengele. For the next three years, he worked on a farm in Bavaria, posing as Fritz Ulmann, a Nazi neurologist whose ID papers he had obtained.
It was an ideal hideout – for a while.
Mengele with Sabine and Andreas in his workshop in Caieiras, Brazil
Mengele was able to see his wife, Irene, who told him she had been interrogated by the US military and that she wanted to leave him.
But he did not feel completely safe. The Allies had begun to try Nazi leaders at Nuremberg – including 20 doctors.
Mengele’s escape from capture was partly due to the fact that the US authorities failed to find him on their first attempt and then gave up. General Telford Taylor, a US prosecutor at Nuremberg, said: ‘Our records show that Mengele died in October 1946.’
Stories of his death obviously suited Mengele. His family endorsed the claim. His wife acted like a widow, wearing only black.
His ghost hung over the courts in Europe and he was a conspicuous absence from the Polish government’s Auschwitz trials in 1947.
Chaotic post-war conditions offered the perfect opportunity to join the flow of emigrants leaving Europe. False identity documents were easily bought on the black market.
Mengele travelled to Genoa in Italy to board a ship to Argentina. He was carrying a Red Cross passport bearing the false name of Helmut Gregor issued by the Swiss consulate.
Argentina’s president Juan Peron welcomed fugitives from the Third Reich – including Adolf Eichmann, the SS lieutenant colonel in charge of transporting Jews to the concentration camps.
Arriving in Buenos Aires, aged 38 and claiming to be a ‘mechanical technician’, Mengele’s first job was as a carpenter. He even received visitors from Europe including his father.
The skull of Mengele, which is stored at the São Paulo Institute for Forensic Medicine in Brazil
Boldly, he went to Switzerland in 1956 where he met his son, Rolf. This, apparently, was the last time Mengele returned to Europe.
A few months later, he felt safe enough to live openly under his real name and applied for an Argentine identity card, using a document supplied by the German embassy. This makes it clear that the German authorities knew Mengele’s whereabouts.
Next, he bought a house and in 1958 married his brother’s widow, Martha, in Uruguay. With a stepson, Mengele seemed to have settled into a comfortable lifestyle.
Back in Europe, Germany was beginning to come to terms with its Nazi past. The Central Office for the Investigation of Nazi Crimes began bringing war criminals to justice.
After receiving information that Mengele’s father had shipped a car to him in Argentina, a German prosecutor obtained an arrest warrant for Mengele in February 1959. The German authorities contacted the embassy in the capital Buenos Aires but its extradition request stalled.
The German ambassador was a former Nazi and claimed that he didn’t remember anything to do with Mengele. By now, Mengele had split from his second wife (who couldn’t bear to live as a fugitive and returned to Europe) and moved to a town in Paraguay.
For more than a year, he was sheltered on the farm of a card-carrying Nazi and obtained Paraguayan citizenship as ‘Jose Mengele’. Even so, he knew it was only a matter of time before Mossad agents might close in.
So at the end of October 1960, he crossed the border into Brazil, where he would spend the next 18 years.
By now, Mengele had a Brazilian identity card under the name Peter Hochbichler, while working as a farm administrator with a couple called Geza and Gitta Stammer who had left Hungary to escape communism.
One farmhand described Mengele as an authoritarian person with a nervous temper who argued a lot and avoided being photographed. The reason for ‘Peter’s’ strange behaviour was revealed by chance.
The Stammers read a newspaper article about Nazi executioners featuring a photo of a young man in his 30s. The face looked quite familiar and Gitta confronted ‘Peter’.
Their guest confessed but chillingly warned that if they reported him to the police, his friends could ‘harm’ them.
Understandably, the Stammers wanted the fugitive Nazi to leave as quickly as possible. But after financial support from him – one payment was of $25,000, which went towards the purchase of their farm – he stayed with them for 13 years, until 1974.
Mengele told Gitta Stammer that he had been in Auschwitz, but never admitted experimenting on human beings.
In 1968, the Stammer family and their guest moved to another estate, where he enjoyed listening to Mozart and wrote and received letters. Mengele was introduced to Austrian-born teacher Liselotte Bossert and her husband Wolfram as a lonely widower called ‘Peter’. They became friends and the Bosserts’ children called him ‘uncle’.
Almost a year later, he confessed to them he was Josef Mengele, the man being sought all over the world; however, he insisted that what was said about him was untrue.
The Bosserts accepted this and they continued to meet every week for dinner.
Now 64 and living alone in the Eldorado neighbourhood on the outskirts of Sao Paulo, Mengele’s health was failing. One of his legs was swollen to twice its size, and he had difficulty walking.
This was to be the last phase of his life. He was addicted to TV soap operas and openly expressed racist views, once saying a series had too many black actors but he watched it for the pleasure of seeing enslaved people mistreated.
His fixer friend Wolfgang Gerhard gave him updated versions of his own Brazilian documents: foreign identity card, work permit and driving licence. Mengele simply replaced Gerhard’s original photos with his own.
In 1976, Mengele had a stroke. A year later, despite being under Mossad’s watch, he was visited by his son Rolf, who used a false passport.
He managed to live on in secrecy for another two years. Then in February 1979 his end came swimming off the coast of Sao Paolo.
Despite the deep fear of ending his existence without love and without affection, he took his last breath surrounded by his faithful protectors who, even in his death, continued to keep his secret.
It was the end of Josef Mengele, but not the end of his story.
Six years later, in 1985, the US, West Germany and Israel announced a coordinated effort to find Mengele and bring him to trial for crimes against humanity.
The main bets were that he was alive, aged 74, and in Paraguay. But a flood of disinformation and fake photos hindered the investigation.
Eventually, the right lead came from Germany after a Mengele family employee bragged about having helped the Nazi doctor by taking money to him in South America. He later claimed he’d taken letters only. A search of the man’s home by police found the name of the Bosserts. It was at this point that Liselotte Bossert helped investigators, revealing that Mengele had drowned six years earlier.
She produced an envelope containing a plastic ID card, driver’s licence and work permit – all with Mengele’s photo, but with Wolfgang Gerhard’s personal information.
The same day, permission was given to exhume the remains from tomb 321 in the Rosario Cemetery in Embu, Brazil.
Armed with hoes and wearing rubber boots and gloves, two gravediggers began the spectacle, digging out the soil. One opened the casket, which was already rotting and starting to crumble, and held out a skull.
It took more than two weeks to get the result. The skeleton had to be glued together, the moustache hair collected and Mengele’s tell-tale front-tooth gap reconstructed.
The Nazi hunter Simon Wiesenthal said he did not believe that the remains were Mengele’s. A former head of Mossad was also sceptical. While one Holocaust survivor Ben Abraham observed: ‘Mengele is so intelligent that I refuse to believe that he left so many photos, documents, and other signs of his passage here, unless it was for the purpose of deceiving us.
‘I can’t believe he drowned. Mengele must be laughing at us right now.’
In Munich, Mengele’s son stated that the remains were those of his father and offered his ‘deepest condolences to all the victims and their relatives’.
The German government contacted British genetic fingerprinting expert Alec Jeffreys who, in 1992, matched the DNA with a sample of Mengele’s son’s blood.
In a deeply ironic postscript, in 2017, a Brazilian doctor asked permission for Mengele’s bones to be taken out of the Forensic Medical Institute in Sao Paulo to be used by medical students in class.
So, seven decades after conducting indescribably inhumane experiments on prisoners in Auschwitz, the Nazi doctor was, himself, the subject of experiments being done in a wholly good cause.
Adapted from Hiding Mengele by Betina Anton (Icon Books, £16.99). Copyright Betina Anton 2025.
To order a copy for £15.29 (offer valid to February 21; UK P&P free on orders over £25) go to www.mailshop.co.uk/books or call 020 3176 2937.