The painting, thought to be a portrait of Lisa Gherardini, the wife of Francesco del Giocondo, is in oil on a white Lombardy poplar panel, and is believed to have been painted between 1503 and 1506. Leonardo may have continued working on it as late as 1517. It was acquired by King Francis I of France and is now the property of the French Republic, on permanent display at the Louvre Museum in Paris since 1797.
The subject's expression, which is frequently described as enigmatic, the monumentality of the composition, the subtle modeling of forms, and the atmospheric illusionism were novel qualities that have contributed to the continuing fascination and study of the work.
Leonardo da Vinci began painting the Mona Lisa in 1503 or 1504 in Florence, Italy. Although the Louvre states that it was "doubtless painted between 1503 and 1506", the art historian Martin Kemp says there is some difficulty in confirming the actual dates with certainty. According to Leonardo's contemporary, Giorgio Vasari, "after he had lingered over it four years, [he] left it unfinished". Leonardo, later in his life, is said to have regretted "never having completed a single work".
In 1516, Leonardo was invited by King François I to work at the Clos Lucé near the king's castle in Amboise. It is believed that he took the Mona Lisa with him and continued to work after he moved to France. Art historian Carmen C. Bambach has concluded that da Vinci probably continued refining the work until 1516 or 1517.
Upon his death, the painting was inherited with other works by his pupil and assistant Salaì. Francis I bought the painting for 4,000 écus and kept it at Palace of Fontainebleau, where it remained until Louis XIV moved the painting to the Palace of Versailles. After the French Revolution, it was moved to the Louvre, but spent a brief period in the bedroom of Napoleon in the Tuileries Palace.
During the Franco-Prussian War (1870–71) it was moved from the Louvre to the Brest Arsenal. During World War II, the painting was again removed from the Louvre and taken safely, first to Château d'Amboise, then to the Loc-Dieu Abbey and Château de Chambord, then finally to the Ingres Museum in Montauban.
In December 2015, it was reported that French scientist Pascal Cotte had found a hidden portrait underneath the surface of the painting using reflective light technology. The portrait is an underlying image of a model looking off to the side. Having been given access to the painting by Louvre in 2004, Cotte spent ten years using layer amplification methods to study the painting. According to Cotte, the underlying image is Leonardo's original Mona Lisa.
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