After the fall of his patron Ludovico Sforza in Milan, Leonardo returned to Florence. He tried to re-establish himself there as a painter but was reported to be ‘very impatient with the brush’, and in 1502 he left Florence to work as a military surveyor to Cesare Borgia, commander of the Papal army.

Leonardo was back in the city the following spring, when the Florentine government commissioned him to paint a huge mural, the Battle of Anghiari. He worked on that painting for the next three years, while also making maps and beginning other paintings, including Mona Lisa and Leda and the Swan.

In 1506 the French occupiers of Milan requested Leonardo’s return to the city, and for two years he travelled repeatedly between Florence and Milan. This was an unsettled period artistically, and Leonardo threw himself into the study of subjects such as anatomy and botany, heralding his greatest scientific achievements over the next five years.