Piero della Francesca (About this sound Pronunciation ; c. 1415 – 12 October 1492) was an Italian painter of the Early Renaissance. As testified by Giorgio Vasari in his Lives of the Most Excellent Painters, Sculptors, and Architects, to contemporaries he was also known as a mathematician and geometer. Nowadays Piero della Francesca is chiefly appreciated for his art. His painting was characterized by its serene humanism, its use of geometric forms and perspective.