There is no evidence that Greta Thunberg is related to the Rothschild banking dynasty, contrary to social media posts targeting the climate activist with the baseless claim. The posts said Thunberg’s great-grandfather was “Joachim Rothschild-Thunberg” but researchers said there was no evidence he existed.
The claim was shared in a lengthy Facebook post published on April 1, 2024.
The post said Swedish climate activist Greta Thunberg is the great-granddaughter of a “Joachim Rothschild-Thunberg”, who it claimed was the illegitimate son of Lionel Walter Rothschild. It added that Lionel Walter acknowledged Joachim in 1928 and adopted him.
“At the age of 26, Joachim Rothschild-Thunberg became one of the most successful bankers in Sweden,” the post said.
The Rothschilds are a famous European banking dynasty often subjected to conspiracy theories, and AFP has previously fact-checked misinformation about the family.
AFP has also debunked falsehoods about Thunberg — herself a frequent target of misinformation.
Nonetheless, the claim was shared elsewhere by Australia-based users on Facebook and social media platform X.
But there is no evidence to support the claim Thunberg is related to the Rothschilds.
Experts told AFP there is also no evidence of Lionel Walter Rothschild having had a son named Joachim, nor evidence of a banker named “Joachim Rothschild-Thunberg” who lived in Sweden.
Thunberg family tree
Åsa Karlsson, editor-in-chief of the Dictionary of Swedish National Biography, told AFP that Thunberg’s grandfather was the well-known actor Olof, or Fritz-Olof Thunberg (archived link).
His death in 2020 was widely reported in Swedish media (archived link).
Greta also posted about her grandfather’s death on her X account (archived link).
Olof Thunberg’s father — Greta’s great-grandfather — was Fritz Thunberg, as stated in Sweden’s 1930 census (archived link).
Fritz Thunberg was born in 1889 in Gotland County, Karlsson said in an April 16 email, pointing to his entry in the Lärbro parish register (archived link).
The record shows Greta’s great-great-grandfather was Carl Gustaf Eriksson — not Lionel Walter Rothschild.
Non-existent ‘great-grandfather’
There is no mention of a “Joachim Rothschild-Thunberg” in Lionel Walter Rothschild’s profiles in Encyclopaedia Britannica, the Rothschild Archive or by the Natural History Museum (archived links here, here and here).
While the Rothschild Archive’s family tree has no record of children by Lionel Walter, online nobility tracker The Peerage states he had one child out of wedlock — Olga Alice Muriel (archived links here and here).
“There is no doubt that Walter Rothschild put himself about a bit,” Tim Amsden, author of The Rothschilds And Tring, told AFP in an April 10 email (archived link).
Amsden was the chairman of a local museum in Tring, where Lionel Walter’s branch of the Rothschild family moved from London (archived link).
There, Rothschild developed an interest in natural science and set up a museum that later became the Museum of Natural History at Tring.
At one point, Rothschild had two mistresses at the same time, Amsden said, citing a biography by the naturalist’s niece, Miriam (archived link).
According to the biography, it was with one of these mistresses, Marie Fredensen, that he had Olga.
“The book does not mention a Joachim, or any Swedish dealings,” Amsden said.
There is also no trace of a “Joachim Rothschild-Thunberg” in Swedish sources.
“The name Rothschild is extremely rare in Sweden,” Karlsson said.
She searched a registry covering all inhabitants in Sweden between 1800 and 1947, but found that “there were only 7 people with the name Rothschild registered.”
“They were all born abroad and came to Sweden during the 20th century. None of them was called Joachim.”