The ‘Ara Pacis Augustae’ (Peace Altar of August), built to commemorate Augustus’ victorious return from Spain and Gaul, stood in antiquity on the Via Flaminia (now the Via del Corso) under what is now the Palazzo Fiano on the corner of the Via in Lucina. Since 2006 the Ara is housed in an airy glass-and-concrete building beside the Tiber; the Museo dell'Ara Pacis, Lungotevere Augusta, Rome.
The lavish sculptural decoration of the Ara Pacis is among the finest examples of Roman art; reliefs representing the ceremonial procession at the altar's dedication are the first in Western art that can strictly be called documentary. The faces are no mere conventional masks, idealized beyond recognition. These are portraits from life and they still retain their freshness showing identifiable individuals in a contemporary event.
Augustus, in his ‘Res Gestae’ (My Deeds), written during the last years of his life says:
“On my return from Spain and Gaul in the consulship of Tiberius Nero and Publius Quintilius [13 BC] after successfully arranging affairs in those provinces, the senate resolved that an altar of the Augustan Peace should be consecrated next to the Campus Martius in honour of my return, and ordered that the magistrates and priests and Vestal virgins should perform an annual sacrifice there.”
The decree of the Senate authorizing the foundation of the Ara Pacis Augustae was passed on July 4, 13 B.C., and it was consecrated on the 30th of January 9 B.C.
(Ovid's Fasti, Book I, 709�722)