Her face is instantly recognizable, yet few people know much about the life of Mona Lisa Gherardini del Giocondo (1479-1542), arguably the most famous artistic subject of all time. But those who want to know more now have a fantastic opportunity, thanks to the recent book “Mona Lisa: A Life Discovered” (Simon & Schuster), in which journalist Dianne Hales reconstructs Lisa’s life, portraying her as the “quintessential woman of her times.”

In the following Failure Interview, Hales explains what might have inspired Leonardo da Vinci to paint Lisa Gherardini, how we know she was Leonardo’s model, and—last but certainly not least—recalls meeting Lisa’s descendants, one of whom has that same unmistakable smile.

Why does the most recognized artistic subject in history remain largely unknown?

Leonardo took the portrait with him when he moved to France in 1516 under the patronage of King Francis I, who purchased the painting after Leonardo’s death. The painting remained in royal palaces for more than three centuries so few people saw it. After the French Revolution, when it was hung in the Louvre, the “people’s museum” identified La Joconde (French for La Gioconda, its Italian name) as the wife of the merchant Francesco del Giocondo.

The del Giocondo family faded from Florentine history, and little was known about Mona (Madame) Lisa Gherardini del Giocondo. After the portrait was stolen in 1911, speculation about the model’s identity sprang up. Among the suggested possibilities were a marchesa, a duchess, a Medici mistress, even Leonardo himself. Only in the last two decades have archival researchers unearthed documents identifying Lisa as the sitter and verifying the dates of her birth and death.

Why did Leonardo choose to paint someone who, as you put it, had “no title, no fortune, [and] no claim to power or prestige”?

There are many theories. Leonardo may have simply needed money, and Lisa’s husband was an affluent merchant who had just bought a new home for his growing family. Francesco may have wanted to honor his wife, who had recently given birth to their second son. But Leonardo turned down more prestigious commissions, so it seems that he deliberately chose to paint Lisa rather than anyone else.

Even though Leonardo was living in Milan during most of Lisa’s life, when he returned to Florence in 1500, his father—who had legal dealings with Francesco del Giocondo—may have introduced his illustrious son to the merchant as a potential patron. It’s possible, but not provable, that Leonardo had seen Lisa in Florence even earlier because her grandparents lived on the same block as Leonardo’s father.

What about her inspired Leonardo, as best you can tell?

I believe Leonardo saw in Lisa Gherardini more than what met others’ eyes. To him, she may have seemed more than a young mother of noble birth married to a blustering businessman. Perhaps the proud “Gherardini” spirit that had characterized her clan for centuries intrigued him. Some art historians speculate that he saw in her the opportunity to share all that he had learned about painting over his long career—and about what it means to be human.

How do we know that Lisa was in fact Leonardo’s subject?

Art historian Giorgio Vasari identified Lisa Gherardini del Giocondo as Leonardo’s subject in his “Lives of the Artists,” published when Lisa’s sons and some of Leonardo’s contemporaries were still alive and could have challenged any misidentification. Speculation about other possible models has run rampant over the centuries, but in 2006 an archivist discovered a margin note in a book that commented on Leonardo’s working on the portrait and was dated as “October 1502.” Everything about this identification has held up to intense scrutiny.

What was Leonardo’s process for painting the Mona Lisa?

We know that Leonardo worked on poplar, which was a popular choice among Florentine artists at the time, and in oils, which were not yet in common use. From the margin note mentioned above, we also know that he first focused on her facial features, leaving the background to be finished later.

Leonardo took the unfinished portrait with him when he was summoned to Milan in 1506 and continued working on it for decades, adding thousands of feather-light brush strokes to create the nuances called sfumatore.

In the course of your research, what discovery was most exciting for you? Most surprising?

The most exciting discoveries came when I actually walked the streets of Mona Lisa’s Florence and visited the places where she lived—from the squalid lane in the Oltrarno where she was born to her grandparents’ home to the street where she lived with her family. I saw the nunneries where she placed her daughters and spent eerie but magical hours in the convent, just steps from her family home, where she lived the last years of her life, died, and was buried. The more time I spent in these places, the more alive this real Renaissance became in my imagination.

The most surprising revelations concerned the lives of Renaissance women—from childhood to adolescence (when most entered arranged marriages) to their daily lives as wives and mothers. Florentine women were not “liberated” in our sense of the word, but they were strong. They not only held up half the sky but served as the glue that held all aspects of Florentine society together. The woman whom Leonardo immortalized was no victim but a fully dimensional, confident, intelligent, intriguing, flesh-and-blood woman.

In the book, you recall meeting what might very well be Lisa’s last living descendants. What was that like? Was there a striking resemblance?

It was a complete delight to meet the Princesses Natalia and Irina Guicciardini Strozzi, the fifteenth generation of Mona Lisa’s grandchildren (on their father’s side), who also are descended from some of Florence’s most prominent noble families. I saw some resemblance, both around the eyes and in the curve of their jawline. However, what impressed me most were their spirit and personalities.

Natalia, a ballerina-turned-actress, is more extroverted and bubbly; her younger sister Irina, more reserved. But both exude such graciousness, warmth, and charm that I had to wonder—although we can never know—if Mona Lisa might have shared their ebullience.

Both of the Strozzi princesses, now in their thirties, have huge, megawatt smiles—the opposite of Mona Lisa’s slight and subtle grin. But their regal father, Principe Girolamo Guicciardini Strozzi, does indeed smile like La Gioconda. I know: I saw it when I presented him with a copy of my book on his renowned ancestress.

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