The Ara Pacis of Rome was built on the area of the "Campo Marzio", close to the "via Flaminia", during the four years going from 13 to 9 before Christ, to celebrate the victories of August in the occidental provinces of the Empire.The same August indicates on the work "Res gestae divi Augusti" the foreseen rituals and the scopes that had led the Senate to build the commemorative altar, which during a large part of the antiquity, as a direct witness of the link between monument and personage, was known as "Ara Pacis Augustae":
"When I came back to Rome from Spain and Gales ... once I had happily closed the enterprises in these provinces,
the Senate decided that for my return the "ara della Pace Augusta" should be consecrated in the "Campo Marzio" and I agreed that in this place the law officers, the priests and the vestal virgins could celebrate an annual sacrifice"
The area of the "Ara Pacis" is limited by a rectangular enclosure in marble with a lot of ornaments of low relief with a width of approximately 10 metres and a length of just one metre more.
The central altar, where were taking place the ritual sacrifices, can be reached through two aperture located at the centre of the shortest sides of the enclosure and is placed in an elevated position with respect to the perimeter of the structure.
The main artistic interest of the "Ara Pacis" is given by the low relief organised in overlap fascia boards and panels that entirely recover the internal and external superficies of the enclosure and part of the central altar.
The celebrative scope of the work is directly testified by the presence of the Imperator August and of Agrippa among the represented personages, but also, on the occidental side, by the scenes dedicated to Enea, considered the parent of the "gens Julia" to whom the same August was belonging to, and by those remembering the divine origin of Rome with the wolf breastfeeding the twins Romulus and Remo under the eye of the father, the god Marte.
The decorations of the "Ara Pacis" are completed by ornaments of naturalistic character, with low relief of plants and small animals and the "Tellus", the divinity representing the personification of peace and prosperity that the empire of Rome was getting prepared to live thanks to the enterprises of August.
According to the study of some documents, it is considered that the original orientation of the work had been chosen also in relation to the big solar meridian called "Horologium" that was already surging in the "Campo Marzio", and which gnomon, nowadays located in "piazza di Montecitorio" and known as the obelisk of Psammetico II, was projecting the own shadow exactly at the centre of the altar every September 23rd, date of birth of the Imperator August.