Bayard, Pierre Terrail, seigneur de, c.1474-1524, French military hero, called le chevalier sans peur et sans reproche [the knight without fear or reproach]. He exhibited bravery and genius as a commander in all the important battles of the Italian Wars, from Fornovo (1495) to the Sesia, in which he was killed. His defense of Mézières (1521) saved central France from an imperial invasion.