The subject in the painting has become a mystery, because Leonardo took great measures to keep the identity of his subject a secret.  He did not write her name down in his notebooks.  He did not share her name publicly.  Even though Leonardo carried her portrait with him for the rest of his life.  Creating the secret of the subject and the 500-year-old mystery.


There are two recorded witnesses of the portrait, during the lifetime of Leonardo da Vinci.  The first is a Florentine Official in 1503.  The second is a Roman Catholic Cardinal in 1517.  Both men visiting the studio of Leonardo.  Record their experience of the painting.


The first witness was Agostino Vespucci, a city official in Florence.  After accepting a commission from the city of Florence, Leonardo was provided a studio.  These accommodations were seen by the city official in 1503.  Vespucci made a memo to himself in the margin spaces of a book.  He records the head in the portrait was not completed.  Unable to recognize an individual.  The city official was told, Leonardo is working on two paintings of "Saint Anne and Lisa del Giocondo."  

The second witness comes from a Catholic Cardinal in 1517.  Leonardo in his final years of life, was working in France under the patronage of the King.  In Rome, the Cardinal d ’Aragona had been instructed by Pope Leo X, Leonardo's former patron, to tour Switzerland, Germany, Belgium, and France, and report his account.  The Cardinal along his tour, stopped at the Court of the King of France.  Where he was given a tour of Leonardo’s studio. 


Rather than delivering the portrait to its owner.  Leonardo had brought the painting with him to France.  Now in the last stage of Leonardo’s life.  The painting could be viewed, nearly indistinguishable, to the way it is seen at the Louvre today.  

The story teller in Leonardo's studio now tailors the subject to the audience of the visiting Cardinal.  The subject previously a merchant from the Republic of Florence for the audience of the city official.  Now transforms into a Medici subject for the Cardinal's report intended for the Medici Pope in Rome.  "A certain Florentine woman done from life at the request of the said magnificent Giuliano de' Medici."

However, there are two faults in the new story.  The Medici did not live in Florence when Leonardo was creating the portrait.  The Medici were driven out of Florence in 1494, not regaining power until 1512.  The Medici were out of power during the majority of the high renaissance and for the painting of Leonardo's portrait.  The second flaw was the storyteller did not understand the Cardinal did not need to be told the identity of the subject in the painting.  He could recognize her for himself.  

In 1517, Cardinal d’Aragona was able to see the finished face in the painting.  More importantly, he was able to recognize the individual.  Leonardo had painted a portrait of the Cardinal's first cousin, Isabella.  Cardinal Luigi d’Aragona and the Marchioness Isabella d’Este shared a grandfather, the King of Naples.    

The Cardinal's secretary records the tale of the Medici subject.  The following day he is instructed by the Cardinal to amend his account.  "There was also a picture in which a certain lady from Lombardy is painted in oil from life, quite beautiful."  He stops in Milan to see Leonardo's Last Supper before joining his cousin Isabella in Lombardy.  Finally completing his grand tour and reporting back to the Papal See. 


The first witness, the city official, was unable to recognize the face because, it was not yet painted.  Making Vespucci not an eye witness to the painting, but an ear witness.  Hearing what he believed to be an accurate story.   The second witness, the Cardinal, saw the painting several years later.  Viewing a finished portrait, the Cardinal recognized an individual he knew.  The Cardinal is the only eyewitness and cousin to the lady in the painting. 


How did an erroneous subject become common knowledge?  The story teller from Leonardo's studio in 1503 could never have suspected, that same city official would befriend the Father of Art History.  Giorgio Vasari was a young teen and art student when he moved in with the Vespucci family in 1524.  The story passed down to the young student as fact.  Vasari published the tale about Leonardo's painting in his renowned text from 1550.  Decades after the death of Leonardo and Isabella.


While, it is widely agreed certain accounts in Vasari's publication are erroneous.  His book created a textual vehicle to communicate visual arts.  Following the introduction of the printing press to western Europe.  His book was published and reproduced, over the next centuries.  The Florentine author over time became known as the Father of Art History.  His collection of stories became a standard text for learning renaissance art, music, theater and architecture.  


As one would expect with a false story, after five hundred years since Vasari’s publication.  No physical evidence has surfaced to support the incorrect subject.  No matching sketch of Lisa by Leonardo exists or any other image of Lisa to compare her with the painting.  There are no letters between Leonardo and Lisa to indicate a relationship or a commission for a portrait.  There is no tangible evidence suggesting Lisa hired any artist of the renaissance. (Leonardo's Riddle)

Accordingly, the Cardinal who saw his cousin in the painting.  Is supported by tangible evidence.  Substantiating the only eye witness of the portrait.  Isabella is known to have been one of the few female interests in Leonardo’s life.  Their relationship is well documented, with letters tracing Leonardo across Italy and France.

In 1491, Isabella's marriage to Francesco II Gonzaga, the Captain of the Papal Armies, unite the powerful Este and Gonzaga Houses in marriage.  Her siblings ruled much of northern Italy and were famous for their patronage of the arts.  Though Isabella's zeal for the creative arts eclipsed the interests of her family and contemporaries.  History deemed the exuberant Marchioness as the First Lady of the Renaissance.   


In 1498 Isabella chose Leonardo to paint her royal portrait.  Isabella first created a contest of painters for the commission.  She compared paintings by the master Bellini with a borrowed portrait from Cecelia Gallerani, known today as, Lady with an Ermine.  Isabella concluded Leonardo to be the winner of her renaissance tournament.  Hiring Leonardo to paint her portrait. 


 In 1500, while Leonardo was living in Isabella's castle in Mantua.  Isabella sat for Leonardo.  She was 25-years-old and pregnant with her first son, the future Duke Federico II Gonzaga.  Leonardo created multiple sketches for Isabella's portrait.  The surviving sketch hangs in the Louvre.  It mirrors the iconic hand gesture and facial features of the painting, that followed.

In the spring Leonardo took Isabella's sketch with him to Venice, to begin the painting.  A record of Isabella's correspondences follows Leonardo across Italy and France.  Ending with the last known correspondence to Mantua in 1517, before Leonardo passes away in France.  Describing the mechanical lion Leonardo created, "that opened, and in the inside it was all blue, which signified love." 

The tangible evidence supports, the only eye witness, and family member of the individual in the painting.  Suggesting the painting is Leonardo’s friend, Isabella d’Este, the renowned patron of the arts from the high renaissance.  Isabella, even without the recognition as the originator of the world’s most famous painting, is celebrated as the First Lady of the Renaissance.


She eagerly supported the genius of Raphael, Mantegna, Ariosto, and Titian, as well as numerous other artists, poets and musicians.  Though it was Leonardo, the diamond in her constellation of artists, Isabella sought to inspire.  Her friendship and faith in Leonardo, the Greatest of Renaissance Masters, is found here in the brushstrokes of this masterpiece.