The Pompeian Styles are four periods which are distinguished in ancient Roman mural painting. They were originally delineated and described by the German archaeologist August Mau, 1840–1909, from the excavation of wall paintings at Pompeii, which is one of the largest group of surviving examples of Roman frescoes. The main purpose of these frescoes was to reduce the claustrophobic interiors of Roman rooms, which were windowless and dark. The paintings, full of color and life, brightened up the interior and made the room feel more spacious.