With the fall (1499) of Milan to the French, Leonardo left that city to seek employment elsewhere: he went first to Mantua and Venice, but by April 1500 he was back in Florence. His stay there was interrupted by time spent working in central Italy as a mapmaker and military engineer for Cesare Borgia. Again in Florence in 1503, Leonardo undertook several highly significant artistic projects, including the Battle of Anghiari mural for the council chamber of the Town Hall, the portrait of Mona Lisa, and the lost Leda and the Swan. At the same time his scientific interests deepened: his concern with anatomy led him to perform dissections, and he undertook a systematic study of the flight of birds.

Leonardo returned to Milan in June 1506, called there to work for the new French government. Except for a brief stay in Florence (1507-08), he remained in Milan for 7 years. The artistic project on which he focused at this time was the equestrian monument to Gian Giacomo Trivulzio, which, like the Sforza monument earlier, was never completed. Meanwhile, Leonardo's scientific research began to dominate his other activities, so much so that his artistic gifts were directed toward scientific illustration; through drawing, he sought to convey his understanding of the structure of things. In 1513 he accompanied Pope Leo X's brother, Giuliano de'Medici, to Rome, where he stayed for 3 years, increasingly absorbed in theoretical research. In 1516-17, Leonardo left Italy forever to become architectural advisor to King Francis I of France, who greatly admired him. Leonardo died at the age of 67 on May 2, 1519, at Cloux, near Amboise, France. . Copyright 1995 by Grolier Electronic Publishing.