Before coming to Canberra, Rome: City and Empire was exhibited at The Frist Center for the Visual Arts in Downtown Nashville, Tennessee. That viewing did not go according to plan; the crowds did not arrive and vibrations from an adjoining building site presented an unacceptable risk to the fragile exhibits so the show closed more than a month early.

The British Museum in London has one of the most extensive collections of art and artefacts from the Classical world with more than 100,000 objects, about 200 of which have been selected for this exhibition. It is a credible exhibition, rather than an incredible exhibition, with none of the famous British Museum masterpieces of Roman art, such as the Portland Vase, the Warren Cup, the Jennings Dog, the Discobolus or the bronze Head of Hypnos, included.

What is included is about 35 marble statues, some quite large, such as that of a Roman magistrate (241cm high) and the monumental head of Empress Faustina I (170cm high). Fragments of wall murals and floor mosaics, objects from daily life and funerary art, numismatics and contents of various hordes are also on display.

Chronologically, the exhibition traces roughly a millennium in the history of the Roman Empire - from a very early ceramic burial urn through to the triumph of Christianity and the destruction of the corrupt and evil pagan Roman Empire.

The conceptual thrust of the exhibition is a focus on the image of imperial Rome, not on the city, but on the vast empire that engulfed and enslaved much of the territory of present-day western Europe, North Africa and the Middle East. Roman military forces imposed social structures with slavery and a system of taxation, a system of devotion to a hierarchy of pagan gods, and overriding oppressive personality cults of the emperors. Those outside the control of Rome were called barbarians and needed to be subjugated and forced into slavery.

The strongest impression of this exhibition is that of imperial propaganda. The work is undoubtedly impressive through scale, craftsmanship and the sense of absolute authority, and reminds me of the ruler cults and their related art under the Nazis and the fascists in Europe. Time has the miraculous quality of sanitising history and, when dealing with ancient Rome, we are encouraged to separate form from content, forget about the atrocities committed and celebrate the frozen perfection in their art.

A few decades ago, a popular construct of world history was to view Rome as bringing enlightenment, law and civilisation to a world of barbarians in the same way British colonists brought civilisation to a continent inhabited by a few nomadic savages. In more contemporary thought, both Roman and British imperial forces did much to destroy indigenous peoples and civilisations through the imposition of their inappropriate authoritarian regimes.

What I find attractive in this exhibition are not the monuments to imperial power and authority, but the more subversive exhibits like those of early Christianity, which testify to the successful struggle by Christians to overthrow the empire from within, the very same empire that crucified their saviour.

There is a gorgeous fourth-century glass goblet with three engraved Biblical scenes, including that of Christ raising Lazarus. Belonging to a similar vintage are gold-glass roundels, which once formed the bases of drinking vessels, especially one showing the Princes of the Apostles, Saints Peter and Paul. As throughout much of the exhibition, the craft aspect of the objects on display is exquisite.

Also very attractive are the accompanying etchings by the great Giovanni Battista Piranesi, strategically positioned on the walls and from the perspective of the 18th century looking back on the glory that once was Rome. Better than anyone else, Piranesi caught the mood of a great empire in decay.

Of the other objects on display, such as the Palmyra funerary busts and the floor mosaics, I would venture to suggest that better examples can be found in the permanent display at the Australian War Memorial in Canberra with the so-called Hagar funerary bust and the Shellal floor mosaic.

If I had to select one object in the exhibition that stopped me in my tracks, it was the Bust of Serapis, about 300 CE, carved out of a single block of lapis lazuli, probably in Egypt. In trade in the ancient world, lapis lazuli was mined in Afghanistan and then carried back to the provinces of the Roman Empire, where sometimes it would be crushed into a pigment to produce a superb blue colour or used as a precious material for carving. The Egyptian god Serapis was worshipped throughout the late Roman world, along with his consort Isis. This a rare and accomplished carving, which I have not seen on display in London and it came as a pleasant surprise.

The British empire, before it too crumbled and collapsed, bought, stole and looted the artefacts of earlier empires. Although this exhibition presents only a tiny cross-section of the British Museum's Roman collection, it bears testimony to the art of empire, with perfectly crafted objects of refined propaganda created by an empire confident in its own supremacy and longevity.