Resolving the Archetypal Mystery of the Mona Lisa

1479 – 1542 · Sitter for the world's most famous portrait

Commissioned subject for the portrait begun in 1503; wife of Florentine silk merchant Francesco del Giocondo

Overview

For centuries, the identity of the woman in the Mona Lisa was a subject of intense speculation, with theories ranging from a disguised self-portrait of Leonardo to a depiction of Isabella d'Este or Pacifica Brandani. However, a clinching archival discovery at the Heidelberg University Library in 2005 provided definitive evidence for the identification as Lisa Gherardini, the wife of Florentine silk merchant Francesco del Giocondo.

This evidence consists of a handwritten marginal note by Agostino Vespucci, a secretary to Niccolò Machiavelli, dated October 1503. Vespucci's note confirms that Leonardo was actively working on "the head of Lisa del Giocondo" at the same time he was preparing for the Battle of Anghiari commission. This firmly aligns with the 1550 account provided by Giorgio Vasari, whose reliability on this point had previously been questioned.

While the identity of the sitter is now considered "beyond doubt," debate continues regarding the specific panel in the Louvre. Leonardo never delivered the painting to the Giocondo family, carrying it with him to France and continuing to work on it as late as 1517. This suggests that while Lisa Gherardini was the original model, the work evolved into a lifelong experimental vehicle for Leonardo's theories on sfumato and the universal maternal figure.

Why It Matters

The resolution of Lisa del Giocondo's identity provides a concrete chronological anchor (1503) for the development of High Renaissance portraiture and validates early historiographic sources that were previously dismissed as anecdotal. The Heidelberg document is one of the most important archival discoveries in modern art history.

Timeline Intersections

1479
Birth of Lisa Gherardini in Florence.
1495
Marriage to Francesco del Giocondo, a successful silk merchant.
1503
Leonardo begins the portrait in Florence shortly after returning from service with Cesare Borgia.
Oct 1503
Agostino Vespucci writes the marginal note confirming Leonardo is working on Lisa's portrait.
1504
Raphael sketches the portrait in Leonardo's studio — between columns no longer visible on the Louvre panel.
1513–17
Leonardo possibly resumes work on the portrait in Rome and France.
1519
Portrait is acquired by King Francis I after Leonardo's death.
1542
Death of Lisa Gherardini.
2005
Heidelberg University discovery of the Vespucci marginal note resolves the sitter debate.

Documentary Anchors

  • The Heidelberg Document (1503) — Marginal note by Agostino Vespucci in a 1477 edition of Cicero, explicitly naming "Lisa del Giocondo."
  • Vasari's Lives (1550) — The first biography to identify the subject as the wife of Francesco del Giocondo.
  • 1525 Inventory of Salai — Lists a painting titled "La Gioconda" as part of the pupil's estate in Milan.
  • Antonio de Beatis Diary (1517) — Records a visit to Leonardo's studio in France where a portrait of a "certain Florentine lady" was shown.
  • Machiavelli's Second Chancellery Records — Confirm Vespucci's position and proximity to Leonardo in 1503.

Open Questions

  • Louvre Panel vs. Isleworth Version: Did Leonardo paint an earlier, "younger" version for the family and keep the Louvre panel for himself?
  • Vespucci's "Head" Remark: Does "painting a head" imply the rest was completed by assistants, or was it simply standard period terminology for portraiture?
  • Salai as a Model: A persistent though widely criticized theory suggests Salai was the model for the final version of the smile.
  • Conservation vs. Original Intent: The yellowing varnish distorts the original color, making technical comparison with the sitter difficult.
  • Isabella d'Este Alternative: Some scholars still view Isabella d'Este as a plausible secondary subject or "ideal" layer in the painting's long evolution.

Key Claims Ledger

ClaimStatus
Identified as Lisa Gherardini by a contemporary eye-witnessSupported
Portrait begun in 1503 to celebrate the birth of a sonSupported
Vespucci note confirms Vasari's 1550 accountSupported
Leonardo kept the painting until his death in 1519Supported
Work was intentionally left unfinished in partsUncertain
Raphael's sketch proves he saw it in 1504Supported
Louvre panel is the same as the Giocondo commissionHighly Probable

Connected Figures