Pietro Perugino was Raphael Sanzio's tutor. He was one of the most successful artists of the Italian Renaissance around 1500. Prominent patrons courted his attention even from some distance from Florence and Perugia, the centers in which he worked. Among his clients were popes, cardinals, dukes and wealthy merchants. Raphael imitated his master closely, and their painting styles are so similar that art historians have found it difficult to determine which were painted by Raphael and which were by his master.