The Ara Pacis Augustae is an altar dedicated to Pax, the Roman goddess of Peace. It was commissioned by the Senate on July 4th 13 BCE to honour the return of Rome's first emperor, Augustus, after three years campaigning in Hispania and Gaul.
The Ara Pacis, which originally stood in the north-eastern corner of the Campus Martius (Field of Mars), was consecrated on January 30th 9 BCE, the fiftieth birthday of Livia, the third wife of Augustus. The Ara Pacis comprised an altar surrounded by a high enclosure, all made of marble and elaborately carved in relief of the highest quality.
The first fragments of the altar were unearthed in the early 16th century in Via in Lucina when Palazzo Fiano was being constructed. Three centuries later, further fragments were found at a nearby location. The pieces were reassembled in 1938 and housed in a custom-built pavilion, the work of the Roman architect Vittorio Ballio Morpurgo (1890-1966).
The pavilion was erected on the west side of the newly-created Piazza Augusto Imperatore, part of Mussolini's massive restructuring of Rome, with the Mausoleum of Augustus at its centre. The creation of the piazza, with new buildings on four sides, involved the wholesale destruction of a densely-populated neighbourhood.
Morpurgo's pavilion was eventually pulled down and replaced by a concrete, glass and steel structure, the work of the American architect Richard Meier.
One of the exterior walls of the museum is inscribed with the Res Gestae Divi Augusti(Deeds of the Divine Augustus), which gives a first-person account of the emperor's life and accomplishments.