A 15th-century letter by Christopher Columbus that found its way in the library of the US Congress years after being stolen from Florence has been returned to Italy, authorities in Rome said Wednesday.
The letter, dating back to 1493, the year following Columbus' first landing in the modern-day Bahamas, is addressed to the kings of European states and informs them about the Italian-born explorer's discovery of the Americas.
Italy's Carabinieri art police said it is worth 1 million euros (1.13 million dollars), but was undersold at auction in the US for 400,000 dollars in 1992. It was later given to the US Congress by an unnamed donor.
The Carabinieri worked closely with US counterparts in the investigation, which started in 2012, Italy Culture Minister Dario Franceschini and the US Ambassador to Italy John R Phillips said in a joint press conference in Rome.
It took decades to realize that the letter had been stolen from Florence's Biblioteca Riccardiana because the original had been replaced with a copy. Another forged document was discovered in another public library in Rome.
Columbus, who sailed on behalf of the Spanish crown, is traditionally credited for being the first Westerner to make contact with indigenous people in the Americas, although there is evidence that Nordic seafarers preceded him in the Middle Ages.