October 1503

Mona Lisa

Agostino Vespucci records Leonardo's work on a portrait of Lisa del Giocondo

The breakthrough was not found in Leonardo's notebooks. It was squeezed into the margin of somebody else's book, printed in 1477.

October 1503, in the margin of a Cicero

In October 1503, the Florentine chancery official Agostino Vespucci wrote a marginal note in his copy of Cicero's Epistolae ad familiares — a 1477 edition — comparing Leonardo da Vinci's practice with that of the ancient painter Apelles.

Reading Cicero's account of Apelles leaving part of a Venus unfinished, Vespucci recognised the same quality in Leonardo and listed contemporary examples.

Among them he named the 'head of Lisa del Giocondo'.

What the note proves, and what it does not

It is the earliest surviving contemporary documentary record of Leonardo working on a portrait of Lisa del Giocondo, and the Louvre identifies that work with the painting now called the Mona Lisa.

Vespucci used neither title, Mona Lisa nor La Gioconda, and did not describe the finished composition. The identification is strongly accepted by the Louvre and most specialists, but the note alone cannot prove every step in the panel's provenance.

The month dates the annotation and confirms the work was under way by then; it is not necessarily the month Leonardo first touched brush to panel.

Three projects in a few lines

The same note mentions Leonardo's Saint Anne and his agreement with Florence's gonfalonier concerning work for the Great Council Hall, now associated with the Battle of Anghiari project.

Armin Schlechter found the annotation while cataloguing Heidelberg University Library's incunabula, and the discovery was first published in May 2005.

The Louvre's current date range for the painting is 1503–1519.

Sources

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How this was checked

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What the sources leave uncertain

The month and wording of the annotation are secure.
The note names a “head of Lisa del Giocondo” but does not use the titles Mona Lisa or La Gioconda. Its identification with the surviving Louvre panel is strongly accepted by the Louvre and most specialists, but the note alone cannot prove every step in the panel’s provenance.
October 1503 dates the annotation and confirms that the work was underway by then; it is not necessarily the month Leonardo first touched brush to panel.