To this day Suetonius's The Twelve Caesars is perhaps the most formidable account of the history of the Julio Claudian (31 BC - 68 AD) and Flavian Dynasties (69 - 96 AD) in Rome. It is through this historical grouping of the two dynasties that an entire artistic tradition devoted to them was spawned.
During the 16th and 17th centuries the depiction of the twelve Caesars arguably served a more historical purpose, while in the 18th and 19th centuries their reproduction was aimed at the tourist trade in Italy at the time. Although most groups depict all twelve emperors, it was also common for artists to produce made-to-measure groups of a patron's favourite emperors. Thus, taking into account Suetonius's scathing accounts on the lives of Caligula, Nero and Domitian, it is conceivable that the original patron for the present group opted to leave out the most undesirable figures for this commission.