Christopher Columbus wasn’t Italian or even originally Catholic but instead a Sephardic Jew likely from Spain who hid his heritage to avoid persecution, a new genetic study suggests.

A decades-long investigation into the famous controversial explorer’s background and conducted by Spanish scientists was meant to shed light on the lengthy debate over where the 15th-century globetrotter was actually born, according to the BBC.

Traditional theories held that Columbus — who was sailing on behalf of Spain when he trekked across the Atlantic in 1492, sparking European interest in the Americas — was born in 1451 in Genoa, an independent republic on Italy’s northwest coast. But many historians questioned that. And new DNA evidence pulled from some of the bones of Columbus’ corpse in Spain’s Seville Cathedral seems to prove them right. “We have DNA from Christopher Columbus, very partial but sufficient,” forensic expert and investigation leader Miguel Lorente said in a documentary called “Columbus DNA: The true origin,” which aired in Spain on Saturday. “We have DNA from Hernando Colón, his son. And both in the Y [male] chromosome and in the mitochondrial DNA [from the mother] of Hernando there are traits compatible with Jewish origin,” Lorente said. Although researchers weren’t positive where Columbus was actually born, they believe it was likely Western Europe, possibly the Spanish city of Valencia.

They believe that Columbus either concealed his Jewish identity or converted to Catholicism to avoid religious persecution.

The findings are based on nearly 22 years’ worth of research that began in 2003, when Lorente, a professor of forensic medicine at Granada University, and historian Marcial Castro exhumed Columbus’ partial remains from the cathedral.

For centuries, countries had argued over his origin, with dozens of conflicting theories that claimed he was born in Poland, Great Britain, Greece, Portugal, Hungary or even Scandinavia. But those ideas — including the novel thought of a Viking Columbus — appear to have been incorrect. The DNA-driven results are “almost absolutely reliable,” Lorente said. The results are consistent with historical records of the era, too, which showed that about 300,000 Jews lived in Spain before Catholic monarchs Isabella and Ferdinand ordered Jews and Muslims to either convert to Catholicism or leave.