The Battle of San Romano (Louvre)

One of three panels celebrating a 1432 Florentine victory over Siena, painted for the Medici palace, Uccello's battle is less a record of war than an experiment in the new geometry of perspective. Broken lances, a fallen soldier, and the bodies of horses are laid out along receding lines like markers on a grid, and the armored knights wheel as if frozen mid-clockwork. Paolo Uccello was so obsessed with perspective that, his biographer Vasari reported, he sat up all night murmuring about its sweetness. The result is part heraldic pageant - patterned horses, fluttering banners - and part eerie, near-abstract puzzle. Two companion panels survive in Florence and London.