Pietro Lorenzetti (c. 1280 Siena-1348? Siena) who according to documentary evidence lived in Siena from 1320 to about 1344, was one of the most important artists of the early 14th century Sencese school. Patterning his work on that of Duccio and Giotto, he incorporated the innovations of Simone Marini and the expressive power of the sculptor Giovanni Pisano (c. 1250-after 1314). In contrast to his brother Ambrogio, Pietro created austere and symmetrical scenes into which he effecively incorporated three - dimensional figures. His painting is distinguished by attentive observation of reality and the changes of light according to the time of day and the season. By the end of his career he had fully developed his talent for narrative, Among his works are the Crucifixion, 1331, San Francesco, Siena, Virgin and Child, 1340, Galleria degli Uffizi, Florence; and plyptych of St. Humilitas, 1341, Centre panel and single scenes, Galleria degli Uffizi, Florence.