The pompa circensis (the procession preceding the wildly popular chariot races in the arena) was both a prized moment of public visibility for the praeses ludorum who conducted the procession and, above all, one of Rome’s most hallowed religious ceremonies, hedged with ritual rules and regulations whose violation could lead to dire consequences (Gailliot). That is, the pompa circensis was fundamentally a pompa deorum, “a teeming procession of ivory gods,” that crowded the circus as it paraded a large number of gods, who as simulacra (anthropomorphic statues) borne on fercula (litters) and as exuviae (symbols, attributes, or “relics”) conveyed in tensae (processional chariots) along the arena floor (Ov. Am. 3.2.61; Ars Amat. 1.47; and Fasti 4.391; and Latham).
In the years just before his assassination in 44 BCE, Julius Caesar received “a tensa and a ferculum in the circus procession,” just like the traditional gods (Suet. Iul. 76.1). Though such honors figured among the reasons for which Caesar was assassinated, Octavian (soon-to-be Augustus) cultivated dynastic connections to his adoptive father in both circus ritual and imagery. After Augustus, however, the pattern of postmortem honors in the circus procession shifted—slightly but importantly (Arena 2009 and 2010). In addition to the traditional tensa, Tiberius provided a statue of deified Augustus borne on a large, decorated cart drawn by a quadriga of elephants in place of a ferculum. On the one hand, this ostentatious vehicle drew a “humble” distinction between the divi and the dei. On the other hand, the currus elephantorum arrogantly and spectacularly asserted raw imperial power. Even though the divus was properly distinguished from the gods, the sheer size and grandeur of this display subverted any humble, pious distinctions between humans and gods.
This humbly arrogant distinction between dei and divi in the pompa circensis may be explained a number of ways. Perhaps the imperial gods were relative as oppose to absolute gods on a kind of sliding scale (Gradel); perhaps they were simply low status gods, and so offered lesser sacrifices by the Arval Brethren (Scheid); or perhaps they only achieved divine status relative to other humans (Iossif and Lorber). Given a relatively firm theoretical distinction between gods and humans (Levene), the ambiguous performance of the imperial gods in the pompa circensis pushed the limit of traditional expectations, while remaining within the bounds of the acceptable. Similar finesses would be employed for members of the imperial household: male member of the imperial domus seems to have rated only an image likely borne on a ferculum, while female members of the imperial household, including empresses at first, received a carpentum (a two-wheeled, roofed cart drawn by mules) to carry the statue, though eventually some empresses themselves earned an elephant cart, albeit a biga instead of a quadriga.
And so, a rough pattern of honors emerged in which the honored imperial dead were internally differentiated among themselves as well as externally distinguished from the traditional gods. Whatever the theological status of these imperial divinities, imperial custom consistently discriminated between imperial and traditional gods, even if this same distinction also made the divi present in a rather more spectacular manner. The humbly arrogant difference seems to have assuaged the religious scruples of the Roman people—that or the threat of massive imperial retaliation—even as it reconfigured, in part and perhaps only for some, the divine world whose goodwill was so important for a flourishing human society.
“Theism” and Related Categories in the Study of Ancient Religions