Leonardo went to Milan c.1482 and remained at the court of Ludovico Sforza for 16 years. In this time he composed the greater part of his Trattato della pittura and the extensive notebooks that demonstrate the marvelous versatility and penetration of his genius. As court artist he also organized elaborate festivals. Severe plagues in 1484 and 1485 drew his attention to problems of town planning, an interest which was revived during his last years in France. Many drawings of plans and elevations for domed churches reflect a concern with architectural problems that must have been stimulated by contact with Bramante during these years. He worked c.1488 on a model for the tambour and dome of the cathedral at Milan. In 1490 he was employed with Francesco di Giorgio as consulting engineer on the restoration of the cathedral at Pavia and later on the cathedral at Piacenza.
In 1483, Leonardo, with his pupil Ambrogio de Predis, was commissioned to execute the famous Madonna of the Rocks. Two versions of the painting exist—one in the Louvre (1483–c.1486), another in the National Gallery, London (1483–1508). Leonardo's fresco of the Last Supper (Milan) was begun c.1495 and completed by 1498. This work is now badly damaged. Leonardo's own experiments with mural painting—in the Last Supper he did not use traditional fresco technique—account in part for its disintegration, which was already noticed by 1517, and subsequent deterioration and repeated restorations obliterated details and individual figures. In 1978 a major (and controversial) restoration was begun, and in 1994–95 protective air-filtration and climate-control equipment were installed. The restoration was completed in 1999, leaving the mural brightened considerably with some details clarified, but also revealing the extensive loss of the original painting. Nonetheless, the composition and general disposition of the figures, in which all lines and attention intersect at the mural's center—the head of Christ outlined against a clear sky and landscape—reveal a power of invention and a sublimity of spiritual content that mark the painting among the world's masterpieces.
While at Ludovico's court Leonardo also worked on an equestrian monument to the duke's father, Francesco Sforza. The work was never cast, and the model, admired by his contemporaries, perished during the French invasion of 1499. In 1511 he undertook a similar work with the commission of an equestrian monument for Gian Giacomo Trivulzio. This work was also never completed and known only through drawings related to the project. After the fall (1499) of Ludovico Sforza, Leonardo left Milan and, following brief sojourns in Mantua and Venice, returned to Florence in 1500.
Back in Florence Leonardo engaged in much theoretical work in mathematics and pursued his anatomical studies at the hospital of Santa Maria Nuova. In 1502 he entered the service of Cesare Borgia as a military engineer. His engagement took him to central Italy to study swamp reclamation projects in Piombino and to tour the cities of Romagna. At Urbino he met Niccolò Machiavelli, who later became a close friend.
By 1503 he was back in Florence, where he was commissioned to execute the fresco of the battle of Anghiari. This work, like its companion piece assigned to Michelangelo, was never completed, and the cartoons were subsequently destroyed. The work exerted enormous influence on later artists, however, and some impression of the original may be had from anonymous copies in the Uffizi and Casa Horne (Florence), from an engraving of 1558 of Lorenzo Zacchia, and from a drawing by Rubens (Louvre). From about this time dates the celebrated Mona Lisa (Louvre), the portrait of the wife of a Florentine merchant.
In 1506, Leonardo returned to Milan, engaged by Charles d'Amboise in the name of the French king, Louis XII. Here he again served as architect and engineer. Gifted with a gargantuan curiosity concerning the physical world, he continued his scientific investigations, concerning himself with problems of geology, botany, hydraulics, and mechanics. In 1510–11 his interest in anatomy quickened considerably. At the same time he was active as painter and sculptor, had many pupils, and profoundly influenced the Milanese painters. A painting generally ascribed to this period is the St. Anne, Mary, and the Child (Louvre), a work that exemplifies Leonardo's handling of sfumato —misty, subtle transitions in tone.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.