Christopher Columbus, the man credited with discovering the New World, spoke Catalan and might have been Jewish, according to a new study published in the US.

Christopher Columbus portrait by Ridolfo Ghirlandaio.

The study by Estelle Irizarry, based on official documents and letters of the explorer, found that Columbus came from the Kingdom of Aragon and his native tongue was Catalan.

Irizarry also concluded that Christopher Columbus's origins were not obscure by chance, but rather the result of the famed explorer's having purposely hid the fact he was a converso, a Jewish convert to Christianity.

"The people who [hid their origins] more and had reason to do so were the Jews," she was quoted by Matzav.com as saying, referring to the forced conversions and mass expulsions of Jews from Spain in the 15th century.

Irizarry, a linguistics professor at Georgetown University, examined Columbus's writings in detail and discovered a simple but important clue that she said had escaped other researchers: a slash symbol - similar to the ones used in Internet addresses - that Columbus employed to indicate pauses in sentences.

The symbol, known as a virgule, did not appear in texts of that era written in Castilian nor in writings from any other country, but only in records and letters from the Catalan-speaking areas of the Iberian peninsula, namely present-day Catalonia and the Balearic Islands, she said,

"The virgules are sort of like Columbus's DNA," she said. "They were a habit of his. Columbus was a punctuator and was one of the few of that era."

The metaphor is the title of Irizarry's book, Christopher Columbus: The DNA of his Writings, in which she pored over the language and syntax the navigator used in more than 100 letters, diaries and documents.

She discovered that the peculiarities of his writing and other linguistic aspects were associated with Ladino, the Jewish ethnolect in late medieval Spain, suggesting that Columbus was in fact Jewish.

"Columbus even punctuated marginal notes and he included copious notes around his pages. In that sense, he followed the punctuation style of the Ladino-speaking scribes," Irizarry said.