Jean-Marc Dreyfus Interview | Alex Gilbert #268

French historian Jean-Marc Dreyfus published The Petiot Affair and the Holocaust (Grasset) in 2025.

The US Congress revisited Credit Suisse’s Nazi accounts in Argentina post-UBS acquisition, the 30th largest financier of nuclear weapons. Could you share insights on your work regarding banks’ economic policies during the occupation?
Jean-Marc Dreyfus: Switzerland did not enact antisemitic decrees or directly seize Jewish property. Instead, Swiss banks were criticized for keeping dormant accounts of Holocaust victims without seeking heirs. Post-war myths exaggerated the amounts involved, though Swiss banks eventually made payments to Holocaust remembrance funds. Banking secrecy, established in 1934 to avoid French tax scandals, was unrelated to the Holocaust. The US later pressured Swiss banks to investigate pre-war accounts, partly using Holocaust memory to expose illicit money. Similar tactics resurfaced with Russian oligarchs’ funds during the Ukraine war, but Swiss banks remain just one part of a global tax haven network.

What about the 12,000 Nazi accounts found in Argentina allegedly containing wealth looted from Jewish victims in the camps? Do you believe that?
J-M.D: That has never been proven. We found some shocking things, though: an account that was funded by a small amount of unpaid royalties of Adolf Hitler’s book, Mein Kampf, for example. The real problem with Credit Suisse was its incredibly poor management. People thought Swiss bankers were geniuses, but they made terrible bets on unprofitable markets, investing in American financial products. During the subprime crisis, they sank like everyone else. The only difference is that they didn’t come clean because they have a tradition of secrecy. That’s what brought Credit Suisse down.

Did you work on Société Générale?
J-M.D: I worked on the entire French banking landscape and specifically on banks that were classified as “Jewish” under exceptional laws. Because a “Jewish bank” doesn’t actually mean anything. A bank isn’t Jewish. The Nazi laws that were integrated into French law defined what a “Jewish bank” was. Essentially, if a bank had a certain percentage of Jewish shareholders or at least one Jewish administrator—according to the classification criteria—then it was considered a Jewish bank. So it’s complicated. Who is considered Jewish? Two Jewish grandparents and at least one Jewish administrator, depending on the classification criteria. That was enough.

Even if all the clients were Catholic?
J-M.D: Yes, they didn’t care about the clients. For Jewish banks, it was about control, not the customers. And so I studied these banks labeled as Jewish and compared them to the myth of the “Jewish bank”—a conspiracy theory that dates back to the early 19th century, which claims that Jews control the banking system and, therefore, the economy, politics, and entire nations. This is an antisemitic myth. There isn’t a single “Jewish bank.” There isn’t just “the Rothschild bank.” People say “the Rothschilds”—which ones? Which branch? Which banker? Which institution? It all has a history. I studied this and found that there were almost no banks of significant importance in France that were classified as Jewish. The Rothschild bank, for instance, wasn’t influential as a banking operator—it was important because it held large stock holdings inherited from the 19th century. The only “Jewish” bank with real significance in the financial sector at that time was Lazard, as an investment bank. Rothschild was more involved in mergers and acquisitions. At the time, it was still a family-run secretariat, not what it later became. That was my dissertation, which was published in 2002.

And now you’re writing a book about Dr. Petiot?
J-M.D: Yes, I wrote a book called The Petiot Affair and the Holocaust, continuing my research on the persecution of Jews in France and the Holocaust in France. Not as an anecdote—because I don’t think it’s just a marginal crime story—but because this history, involving France’s most notorious serial killer, tells us something about the persecution of Jews. Most of his victims were Jewish. It fits into a broader context—networks, modes of persecution. I wanted to write a historical study of the case—surprisingly, none existed before, only journalistic accounts and novels. People today, unless they’re over 45 or 50, don’t know who Dr. Petiot was. So I searched the archives—because that’s what historians do best. So, I found 5,000 to 6,000 pages of archives, including police and judicial records, as well as press reports and some scattered personal documents. This allowed me to write, for the first time, the true story of Dr. Petiot—not the mythologized version that became fossilized in 1946-47. The narrative presented at the time of the trial has remained strangely unchanged. It has been copied from one book to another, even in the most recent ones. So, I tried to go beyond this fossilized and crystallized story to uncover the real truth—and I was absolutely stunned. If I had made up this story, it wouldn’t have been published because it’s completely unbelievable.

What did you discover?
J-M.D: I’m not making any shocking revelations, like saying Petiot was transgender or Jewish. In fact, the book isn’t centered on Petiot’s personality. That’s surprising, but I’m not a historian of psychiatry. I can’t tell you if he had a split personality, if he was schizophrenic, etc. Was he insane? Yes, certainly. Very much so. Did he have control over his actions? Yes, and the justice system deemed him fit to stand trial. Otherwise, he wouldn’t have been judged. What I discovered is that this doctor was at the center of a massive network of people—informants, black-market dealers. He was a drug dealer, likely one of the biggest suppliers in Paris at the time. He wrote fake prescriptions that were sold for 100 francs, which was quite expensive. So, he was involved in a network of drug users that included artists and prostitutes. The drug scene in Paris at the time was very small. He was also connected to the medical community. Fellow doctors would send him clients. He was linked to an informal network of Jews in Paris trying to escape the city. And what fascinated me was that these Jews, mostly, were German Jews. That had never been described before. These were German Jewish refugees. In the standard literature—tell me if I’m getting too detailed—in this crystallized, fossilized literature, only three figures are usually mentioned:
*The furrier neighbor, Gushinov, who is said to be Polish but was actually from Ukraine.
*Braunberger, a doctor who disappeared—he was related to the film producer Braunberger, possibly the uncle of the man who later became a major figure in the French New Wave cinema, originally from Alsace.
*Ivan Dreyfus, an Alsatian Jew and a resistance member, was taken from the Compiègne camp by the Gestapo and sent into Petiot’s hands to determine if Petiot was really helping Jews escape the Nazis. Poor Ivan Dreyfus never reappeared. He vanished into Petiot’s grasp. But in reality, those are just three victims. There were actually 26—likely 27, since one victim was almost certainly killed by Petiot, though the justice system didn’t officially confirm it. So, at least 27 victims. And I wanted to find out who the others were. There were two main categories: German Jews—three families of German Jewish refugees who fled to the Netherlands in the 1930s but didn’t make it to France until later. They didn’t know each other. They were part of a broader German Jewish diaspora that spread worldwide in the 1930s.

Typically, one brother ended up in Palestine under the British Mandate, another in La Paz, Bolivia, and another in Paris. We know that the majority of German Jews survived. It’s one of history’s great paradoxes—75% of them survived, but in exile, spread across the globe.

Can you repeat that statistic?
J-M.D: Yes, 75% of German Jews—meaning Jews living in Germany in 1933—survived the Holocaust.

It’s a paradox, but the same percentage applies to French Jews: 75% of them survived.
J-M.D: By contrast, only 25% of Dutch Jews survived. You’d think German Jews, as the Nazis’ first victims, would have been wiped out more completely. But no—most of them managed to flee, which wasn’t the case for French Jews. The French couldn’t leave as easily. You had to leave before the war broke out. After 1939, escaping Europe became extremely difficult—almost impossible. That’s incredible information. I had never thought about it that way. So, these German Jews were in the Netherlands, moving around Western Europe. In the 1930s, you see a son moving to Paris to join his father. I traced all of this. They were fairly typical German Jews—middle to upper-middle class, highly educated, multilingual, art collectors, and somewhat wealthy.
These families had been well-off for two or three generations. They had grandmothers who—this is a very typical pattern. And what’s astonishing is that they arrived in France illegally in late June or early July 1942. Isn’t that incredible? Historians have described this phenomenon—the desperate southward flight of those who could afford it, taking immense risks, trying to reach Portugal, Switzerland, or the unoccupied zone of France. And why did they arrive at that moment? Because the mass roundups in the Netherlands started a month earlier than in Paris. The deportations had begun in the Netherlands, so they fled south. Where could they go? The Netherlands had no safe escape routes to England. It was too dangerous—there were no ships to Britain. They had to travel by land. They moved from the Netherlands to Belgium, then into France. Crossing two borders, they had to buy fake papers, find people to help them—it’s fascinating to trace these networks. Some of them reached Marseille. Others ended up in Paris. And since they were upper-class, they had means. They had fake papers. They settled in the 6th arrondissement, at a hotel they knew—the Hôtel du Danube on Rue Jacob, which still exists today. They got there and started searching for contacts. They reached out to the people they knew in Paris. In July 1942, they weren’t caught in the Vel d’Hiv roundup because they weren’t on the lists—they had just arrived. So, what did they do? The first networks they turned to were business connections. One of them traveled to Évreux, where he had a contact in the timber trade, asking for a way to escape. They also sought out other German Jews they had known in the 1930s—cousins, acquaintances—who were already in Paris.
And that’s how they were introduced to a woman—a recruiter for Dr. Petiot. I have an entire chapter on this woman, Eriane Caron, an incredible character. If I had written about her without basing it on archives, publishers would have rejected my manuscript as unbelievable. Eriane Caron was Petiot’s main recruiter.

When you say “recruiter,” you mean for victims, not for the resistance?
J-M.D: Yes, exactly. She lured Jews into Petiot’s trap. Petiot told them he could smuggle them to South America. The cost was 58,000 francs—a huge sum. He told them to bring all their valuables, to sew their money into their clothes. And it was Caron who arranged all of this. She was a Jewish woman who claimed to be from Vienna but was actually from Czernowitz, in Romania. There are many incredible figures in this story. Dr. Petiot was at the center of multiple networks that intersected during the chaotic years of the occupation. What’s certain is that he was not part of the resistance. This is not true. It was one of the major issues after the Liberation for members of the Resistance to prove that they had never been part of it. So all the well-known resistance fighters who emerged in 1944 were interrogated by the judiciary. All of them. Philippe Brossolette, we have the entire list. And they were absolutely outraged. “How dare you? I, who have just returned from the camps, who led such and such a network—how could I have worked with Dr. Petiot?” Because Dr. Petiot always claimed that he was a resistance fighter. Later, there was talk of Dr. Petiot having ties with the collaboration and the German police. But again, in the investigation, this did not hold up. There was nothing. No connection at all. And all the major collaborators—Bonny, Laffont, and the others—were tried after the war. And not a single one… Not a single one said, “No, no, I worked with Dr. Petiot.” So he was neither a collaborator nor a resistance fighter.

What role did Petiot’s trial in 1946 play in revealing the persecution of Jews? And how does your approach differ from previous accounts?
J-M.D: That’s what interested me. A hypothesis—the kind that every good history student is asked to formulate in their first year. What is your hypothesis? What are you going to demonstrate in your dissertation? The good old methods from Sorbonne-style training. I had to find one to justify this so-called morbid curiosity about Dr. Petiot. So, here’s what I came up with. My hypothesis is that at the Petiot trial, which took place in March and early April 1946, lasting three weeks and captivating the public—with an extraordinarily extensive media coverage, including internationally—it was covered daily in The New York Times. Well, at this trial, the persecution of French Jews was described in detail. Whereas historians have always debated and claimed that this was the period of silence, the great silence about the Holocaust in France—until the 1970s, until an awakening of awareness, etc. It’s a debated topic, and I won’t go into details. But what I show—and it holds up, I demonstrate it in the book—is that at this trial, which had 85 witnesses, lasted three weeks, and had detailed media coverage, the persecution of French Jews was thoroughly described: border crossings, hidden children, the major roundups of the summer of ’42—what was not yet called the Vel’ d’Hiv roundup—the looting, all were described. And the defense lawyers, in order to highlight the fate of the victimized families, already had, at that time, the lists of convoys from Drancy. They referred to specific convoys to account for the deported family members. So, that was my starting hypothesis, which I believe I manage to demonstrate in the book.

Ed Gein, the American criminal who exhumed corpses and collected Nazi memorabilia, appears in an international gloomy exhibition, Monsters, Mindhunter, The Silence of the Lambs and The Texas Chainsaw Massacre. Was Dr. Petiot’s case in France, deeply embedded in popular culture too ?
J-M.D: I wonder whether Petiot really became a figure of French popular culture. There have been many references; he appears here and there. But he’s not Jack the Ripper, nor is he this Mr. Gein or Mengele—I don’t think so. I believe there was a time, in the ’50s, ’60s, ’70s, when he was still remembered. There were many people who were interested. And the references in the Petiot case to other infamous figures in history—those are, on one hand, the great serial killers of France’s past. He was compared to Landru, the equivalent of Petiot during World War I, who murdered war widows and burned the bodies, just like Petiot. And then there was Weidmann. Weidmann is largely forgotten today, but he was very well known. He was the last person to be publicly executed, in June 1939. My next book will be about Weidmann. I’m starting research on it because I feel like there’s something there. He was German, too. He had been imprisoned before the war, before the concentration camps. He was considered anti-Nazi, although his family was Nazi. There is something intriguing about the Weidmann case in June 1939, in Versailles prison. It tells me there’s a story worth uncovering, and I’m doing the same thing I did before.

Do you see yourself in the tradition of Truman Capote, the founder of New journalism ?
J-M.D: I would like that. But, first of all, I didn’t become friends with Dr. Petiot, unlike Truman Capote in In Cold Blood. And in fact, it’s not really about the divide between literature and journalism. I’m still a historian, trained in a very classical manner in political history.

This is also the case with Hannah Arendt and later with Emmanuel Carrère. New journalism is rather about bringing knowledge into the press.
J-M.D: Maybe new journalism is better understood as intellectual journalism, as Americans say—a concept that remains elusive in France. We don’t have a New York Review of Books equivalent in France, though there have been many attempts. Other countries have it—the Netherlands, Germany—but not France. I consider myself, rather, as a historian of the Holocaust, from a younger generation, though not that young. I have many colleagues younger than me who are searching for new ways of writing. I’m not talking about literature—I don’t consider myself a writer—but ways to convey history and memory. Others are trying as well. And yes, I tried to write this not in a literary way, but in a journalistic way, while maintaining absolute historical rigor. I didn’t invent a single dialogue, though I was tempted to. I didn’t invent a single sentence or line of dialogue.

Does Dr. Petiot have a modern-day equivalent?
J-M.D: That’s a good question. Yes, what his case tells us about the present is the extraordinary fascination—one that isn’t new, dating back at least 30 years in France and the Western world—with serial killers. In my introduction, I point out that the term “serial killer” didn’t exist at the time. The concept didn’t exist in France then. It only entered the vocabulary in the late 1980s, imported from the US. And now, there is an absolute fascination with serial killers—just look at Netflix. The serial killer has truly become a figure of popular and media representations—something that sells and captivates audiences.