The Battle of Anghiari (Leonardo da Vinci)
In 1504 Leonardo da Vinci was given the commission by gonfaloniere Piero Soderini, a contract signed by Niccolò Machiavelli, to decorate the Hall of Five Hundred. At the same time his rival Michelangelo, who had just finished his "David", was designated the opposite wall. This was the only time that Leonardo da Vinci and Michelangelo worked together on the same project. The painting of Michelangelo depicted an episode from the Battle of Cascina, when a group of bathing soldiers was surprised by the enemy. However Michelangelo did not stay in Florence long enough to complete the project. He was able to finish his cartoon, but only began the painting. He was invited back to Rome in 1505 by the newly appointed Pope Julius II and was commissioned to build the Pope's tomb.
Medici Chapel
Though it was vaulted over by 1524, the ambitious projects of its sculpture and the intervention of events, such as the temporary exile of the Medici (1527), the death of Giulio, now Pope Clement VII and the permanent departure of Michelangelo for Rome in 1534, meant that Michelangelo never finished it. Though most of the statues had been carved by the time of Michelangelo's departure, they had not been put in place, being left in disarray across the chapel, and later installed by Niccolò Tribolo in 1545. By order of Cosimo I, Giorgio Vasari and Bartolomeo Ammannati finished the work by 1555.