The Dream of Constantine

Inside a great peaked tent the emperor Constantine sleeps on the eve of battle, watched by two guards and a servant, when an angel plunges from the upper left in steep foreshortening to promise him victory under the sign of the Cross. Part of Piero's fresco cycle of the Legend of the True Cross at San Francesco in Arezzo - drawn from the medieval Golden Legend - it is among the first convincing night scenes in Western art: the angel's radiance alone lights the tent's folds, the armor, the sleeper's face. Piero makes even supernatural light obey physical rule.