The Tellus Relief on the Ara Pacis in Rome, June 1995

The Ara Pacis Augustae (Latin, "Altar of Majestic Peace"; commonly shortened to Ara Pacis) is an altar to Peace, envisioned as a Roman goddess. It was commissioned by (or for) the Roman emperor Augustus, consecrated on 4 July 13 BC by the Senate to celebrate the peace established in the Empire after Augustus's victories in Gaul and Hispania. It was dedicated on 30 January 9 BC. The altar was meant to be a vision of the Roman civil religion. It sought to portray the peace and prosperity enjoyed as a result of the Pax Romana (Latin, "Roman peace") brought about by the military supremacy of the Roman empire.

The Ara Pacis was elaborately and finely sculpted entirely in gleaming white marble, depicting scenes of traditional Roman piety, in which the Emperor and his family were portrayed in the act of offering sacrifices to the gods. Various figures bring forth cattle to be sacrificed. Some have their togas drawn over their heads, like a hood; this signifies that they are acting in their official capacity as priests. Others wear laurel crowns, traditional symbols of victory. Men, women, and children all approach the gods. The Altar is considered a masterpiece of Roman sculpture; the figures in the procession are not idealised types, as are typically found in Greek sculpture, but rather recognizable portraits of individuals.

As it stands today, the Ara is a combination of original fragments found on the original site and kept in Rome, and of plaster casts of original fragments now in foreign museums, including the Louvre in Paris.

Text from: en.wikipedia.org/wiki/Ara_Pacis