A note written in a manuscript in the library confirmed the account of da Vinci's first biographer, Giorgio Vasari: that the sitter was a merchant's wife, Lisa Gherardini.
But the Mona Lisa — said by the Louvre to be a portrait of Lisa Gherardini, the wife of a Florentine silk merchant — and additional works by Leonardo still have other secrets to tell.
That is similar to one that da Vinci included in a sketch of a fortress contested by Pisa and Florence in the war that flared between them in 1503 (around the time he was painting Gherardini).