Autumn 1944. As Allied troops swept through the Vosges mountains of northeastern France, they stumbled upon a scene that defied comprehension. In the Natzweiler-Struthof concentration camp, they found a furnace, a gas chamber, an autopsy room—and in Strasbourg, containers filled with the remains of human bodies. These atrocities bore the signature of one man: Heinrich Himmler. They were the traces of medical experiments on human guinea pigs, ordered by the head of the SS himself.

The people who committed these crimes were not ordinary soldiers. They were scientists—members of one of the most active yet most mysterious organizations of the Third Reich: the Ahnenerbe. This was science used for a criminal program, a program for enslavement and extermination.

Thanks to the Ahnenerbe, scientists were able to carry out experiments on human guinea pigs. On Himmler’s orders, Ahnenerbe scholars carried out remote digs and expeditions going as far as Tibet. But they also looked for medical cures through some atrocious experiments. All these researchers were dedicated Nazis whose goal was to prove the supremacy of the Aryan race—a supposed race of tall, powerful men, and the only acceptable race in the eyes of Adolf Hitler.

What were they looking for? And what methods did they use? What did they really find? Why did they go to Tibet? And what did Adolf Hitler think of it all?

By searching through previously unseen SS archive footage and consulting the latest historical research, we’ve managed to map out the history of the Ahnenerbe—an obscure organization that was behind some of the most sadistic crimes of the Third Reich. Here is the horrific story of these black-coated scientists.

This is the only concentration camp built in France. It’s located near Strasbourg and was called Natzweiler-Struthof. This is where some of the most murderous chapters in the history of the Ahnenerbe took place. We met up there with historian Frédéric Nur.

“It’s very difficult because it’s a beautiful sunny day. There are flowers and birds and it’s hard to imagine that there were 17 barracks behind us on the terraces. There were 6,000 men in the same place packed together without food who had to work all day. That’s a tough reality to imagine today.”

And yet it was the same story in every part of this camp. One of the most striking places is right here in this building where several rooms were set aside for medical experiments on human guinea pigs.

This room was for experiments and dissections and is located in one of the wings of the building which has a dreadful history because the crematorium was in the center of the building and the whole of the right wing was used by the doctors. They even had a lovely office for when they came from Strasbourg to work in Natzweiler—with lovely wallpaper on the walls just like at the university. Then opposite the office, in stark contrast, was the room where the human guinea pigs slept on punctured wooden bunks and where they were subjected to horrific pain.

From 1942 to 1944, the Natzweiler-Struthof camp would be the theater for the Ahnenerbe scientists’ crimes. This top-secret scientific organization’s sole aim was to perform experiments into new medical treatments and to discover the origins of the Aryan race—a race that Nazis considered to be superior to any other.

The brainchild of this scientific organization was a notorious man: Heinrich Himmler, Adolf Hitler’s right-hand man. On the 1st of July 1935, the head of the SS officially created the Ahnenerbe in Berlin. Himmler supported research and was committed to the work he considered essential. He also gave jobs to scientists so they could carry out research that would benefit his political strategy.

But Himmler wasn’t alone. He was supported by certain Wolfram Sievers. Sievers was an ingenious and inventive manager of scientists. But he was also an opportunist and a man obsessed with order. This man who lacked any scruples directed the Ahnenerbe until the end of the war. He was behind the radicalization of medical research in the early 1940s.

This terrible shift was triggered by a meeting at the highest level on the evening of November 23rd, 1941. Despite the war, the Reich University of Strasbourg organized a ceremonial dinner. Wolfram Sievers, the head of the Ahnenerbe, was one of the guests of honor. Most of the faculty were actually SS and many of them had an association with the Ahnenerbe.

That evening, Sievers met August Hirt. Thanks to extensive archive research, German researcher Julien Reitzenstein has reconstructed this encounter which had dramatic consequences.

“In the archives, we see that Sievers put a note beside all the people he talked to. And at one of the tables beside his was the new director of the Strasbourg Institute of Anatomy, Professor August Hirt.”

Dr. Hirt, who had been disfigured during the First World War, was a reputed scientist thanks to his work on a new type of microscope. He was successful in his field and he was even more successful because he was an SS officer. So that political career actually enhanced his scientific career.

When he met Sievers, Hirt was working on a potential treatment to counter the effects of the fatal mustard gas used during the First World War. The German population was very fearful of an Allied attack using this type of chemical weapon. The eminent scientist profited from the situation to join the Ahnenerbe, for it was a chance to boost his own reputation and enjoy a better research facility.

Dr. Hirt wanted to test his potential cure on human guinea pigs. Sievers asked him for permission and the head of the SS was clear. He gave carte blanche to the doctors and the SS would give Hirt everything he needed. Himmler even said that if Hirt needed human guinea pigs, he could have access to the concentration camps. He just needed to say the word.

Hirt and Sievers would use this official authorization a few months later, in 1942.

That summer, on the front, the army of the Third Reich started to withdraw for the first time. All Germans of fighting age were called up—but not Sievers or Hirt. In retrospect, and in view of certain documents from back then, we realized that above all, Hirt and his collaborators wanted to avoid being sent to the front. The irony of this story, albeit with its tragic consequences, is that the heroes themselves didn’t go to war.

Thanks to these two unscrupulous opportunists, the Ahnenerbe descended into the horror of experiments on human guinea pigs. Of all the departments in the organization, the most important was Section H. H for Hirt. The anatomist chose the Natzweiler-Struthof camp for his experiments.

This is the only concentration camp in France. It was a concentration camp in all its horror—with the violence, the hunger, the ovens, the prison, and the gas chamber. In just three years, almost 52,000 prisoners from across Europe were locked up and enclosed by this barbed wire. They worked in a stone quarry until they died from exhaustion. More than 22,000 people lost their lives in these hills.

Right at the bottom of the camp, this building still bears the macabre traces of Nazi atrocities—and in particular a room that was arranged specially for Dr. Hirt. This is the room where autopsies and dissections by SS doctors were carried out. This room was preserved after the liberation. It’s one of the most shocking in the camp.

It was here and in the rooms next door where the main Ahnenerbe experiments were carried out, and in particular the tests on mustard gas. The experiments began with the application of a few drops of poison in liquid form on the prisoner’s forearm. Then they would try out Hirt’s vitamin-based therapeutic cures to see what happened.

Hirt and his assistants carried out several tests on around 15 prisoners. These prisoners were volunteers, tempted by the promise they would be treated like SS troops. Hirt had wanted the participants to be in a comparable state to the soldiers on the front. These prisoners suffered terrible wounds all over their bodies and three subsequently died.

Today we don’t know exactly how many prisoners from Natzweiler-Struthof passed through Dr. Hirt’s hands. This evil doctor never found an antidote to mustard gas. But these dreadful experiments were far from being isolated incidents.

Since the spring of 1942, Jews were being exterminated in huge numbers in death camps in Poland in the name of what the Nazis referred to as the Final Solution. Experiments on human guinea pigs became more widespread. They happened all over Europe, in dozens of camps located in countries including Germany, Poland, and the Netherlands.

These experiments were encouraged by the Ahnenerbe and the Nazi system as a whole, which led to increasing numbers being carried out in the camps without exception. And by that I mean that each camp had its official doctor or doctors who carried out all kinds of experiments. The most barbaric of these doctors were Carl Clauberg in Ravensbrück, Erwin Ding-Schuler in Buchenwald, and Josef Mengele in Auschwitz.

The aim of the doctor was to save the race. And if in order to do that they had to sacrifice a few individuals who weren’t part of that race, it was worth it.

Why did these doctors go beyond all limits in their grisly work? To try and understand, we have to go back to the roots of the evil—a decade earlier, when scientists of all kinds dedicated their skills to the service of Adolf Hitler.

Berlin, March 1933. The National Socialist Party, the NSDAP, won a majority. The new chancellor, Adolf Hitler, took power and a dictatorship was soon established in the country. At that time, German scientists were among the best in the world in many different areas of expertise. German scholars had won Nobel prizes in a range of fields including physics, chemistry, and elsewhere.

A majority of Jewish scientists had left Germany, as Albert Einstein did in October 1933. But some very talented people remained—and among them, most of the intellectuals and doctors had joined the National Socialists. It was a young generation. They were people who were 20 to 30 years old, educated people, very intelligent folk. They were opportunists who saw their chance for an amazing career, and people who had strong ideological convictions.

Hitler planned to take advantage of this pool of young talent. Hitler was not a scientist, and while he was not interested in science per se, he nevertheless gave a lot of support to what we would call military science. The Führer needed intellectuals, but their research had to be in the best interests of industry and serve the power of the Third Reich.

Behind the scenes, Hitler had already started preparing for war and what he called the Great Reich. Far from being a stranger to science, Hitler believed that scientific research was a means to serve and underpin his racial ideology. The idea was that the human races—in inverted commas—were not all equal. That some were superior to others, and some races in humanity—once again in inverted commas—were inferior.

The so-called superior race was the Aryan race. An ancient concept, but one Hitler had been using since 1924 when he wrote Mein Kampf, or My Struggle. The Nazis started pursuing the impossible in a quest for this race they themselves were incapable of defining with any precision. They drew up physical and genealogical pseudo-criteria, and to them, anyone who didn’t meet these criteria did not deserve to live.

To pursue the objectives fixed by National Socialism, areas of research such as medicine, racial anthropology, and racial hygiene became very important. Right from the start of the dictatorship, doctors were being used for this means. They would be tasked with establishing policies of so-called racial hygiene—or sterilization and abortion programs, and later euthanasia.

The doctors had to purify the Aryan race with its Teutonic and Nordic origins. Their ideal was blonde hair and light-colored eyes. In addition to undesirable physical criteria were what the Nazis considered to be dangerous parasites: handicapped people, homosexuals, gypsies, Jews. But at the time, the Third Reich did not yet know what to do with these impure individuals.

To them, it wasn’t speculation. It was a reality that biology could scientifically prove and justify. Doctors and specifically also anatomists became involved in the creation of a medicalized politics, basically, that gave the foundation for the biology of racism.

To Himmler, Hitler’s faithful companion, natural and human sciences had a fundamental role in Aryan selection and the extension of the Third Reich. In this context, the head of the SS decided to create his own research center to establish the origins of the Aryan race. Its name was the Ahnenerbe, and its symbol a tree.

“They set off in a quest, like a quest for the Holy Grail, to track down these ancestors and establish where they were.”

From anthropology to archaeology via the natural sciences, Himmler’s center brought together a wide range of research. But what Himmler called the sciences was mostly pseudoscience, because this research was guided by Nazi ideology. The Ahnenerbe scholars were fanatics and criminals—and their story shows what can happen in the absence of legal, financial, and ethical limits.

So we ask you: should science ever be placed in service of ideology, or must it remain accountable to humanity first?