The Florentine painter Andrea del Castagno (c. 1419-1457) was a central figure of the Italian Renaissance, and his work appears in every major survey textbook on the period. Giorgio Vasari described him a master of drawing and a constant innovator. Vasari also however claimed that Andrea was a cold-blooded assassin, a man who left a self-portrait as Judas and who had murdered a fellow painter to obtain the secret of painting in oil. When Andrea del...