Although the ancient Roman religion might seem a far cry from today';s contemporary context, in reality Roman religion continues to inform and shape Western culture to this day (the celebration of Christmas being one example). While there are a number of literary sources which provide contemporary scholars with information about Roman religions, both in terms of belief and practice, this religions information is encoded into the landscape and physical space of Rome itself, from the layout of its forums to the sculptures which adorn its altars. By examining three such sources in detail, the Ara Pacis, the Forum of Augustus, and the grove of the Arval Brothers, one will be able to understand how Roman religion permeated Roman social and political identity and organizations, and furthermore, how these concurrent strains of identity-formation and power relations etched themselves into the very physical objects left behind to be discovered and discussed by contemporary historians.
Before examining some of the non-literary sources of contemporary knowledge of Roman religion in detail, it is necessary to first outline the ideal methodological approach to the task at hand, if only because it requires some special knowledge and consideration that sets it apart from strictly literary engagements with the general topic. Firstly, one must recognize that although "we are certainly not illiterate when it comes to Roman art,  we do not come close to the fluency of a 'native viewer.'"
For example, it is all too common to approach Roman art and non-literary culture from a rather literal perspective, which fails to recognize that, for example, "a society that consistently for centuries depicts the sun as a youthful beardless male charioteer rather than as a fiery orb  clearly has a complexly coded visual systems" such that:
In Roman art what you see is often not what you get, for despite the way they depicted the sun, it is quite clear that most Romans did not think that it was a youthful male charioteer, just as they did not think that Eternity was a woman bearing the severed heads of the sun and the moon on her outstretched hands; it was simply the way they visualized the concept. In other words, they thought of the sun as the youthful charioteer when they visualized him in art, but not when they conceptualized him as a cosmic body.
While recognizing the "obvious difference between image and concept" is in many ways a basic concept in any art or cultural criticism, it takes on new importance in the field of Roman religion because of the way the religion was so deeply engrained in the social and political fabric of life.
Religion "was  a major aspect of the changing relationship between Rome and her empire" over the course of the city's development, because it offered a means of defining Roman culture and identity as the state underwent the painful and tumultuous "creation of a strong centralized political system and  the sometimes difficult moves towards the integration of the state."
As such, religious identity was encoded into not just strictly religious texts, but also the aesthetics of the city itself, it ornamentation, and the art of the empire in general.
Thus, the first step in constructing the ideal methodological approach for this study involves a recognition that the analysis and discussion of non-literary sources of the contemporary world's knowledge of Roman religion must necessarily engage in some visual criticism of the particular objects under discussion that goes beyond a mere recapitulation of the specific visual codes represented, because these codes must be considered in a larger, synchronically meaningful context. This is due to the fact "that verbal and visual modes of communication differ too fundamentally to be equated," as "the primary dimension of verbal communication is temporal, not spatial, whereas visual communication is spatially organized, but not temporal."
That is to say, visual communication must be understood for the way it creates meaning out of the spatial juxtaposition of images, rather than the kind of temporal progression dominant in language; although visual communication can and frequently does feature a kind of temporal narration, such as the Western tendency to view the movement of images from left to right, this temporal element nevertheless remains subservient to the spatial orientation of the image's various elements, because without understanding this spatial definition, any temporal, narrative meaning remains hidden.
This means that when one is confronted with a particular image, it is necessary to consider how the context of that image informs its interpretation, and the particular connotation associated with it. For example, "one can find certain conventions for the depiction of radiance described as 'solar' or typical of Sol," the Latin name for the sun, "and thus give the bearer a 'solar aspect,' despite the fact that the particular convention under discussion might be one that was actually never used for Sol."
Thus, one must consider the unique way visual communication functions synchronically, rather than diachronically, in its construction of meaning in order to differentiate between different uses of similar imagery and visual cues. This will become important when considering the convergence of the religious and political in non-literary sources of information on Roman religion, because frequently these sources deploy visual codes and representations that have multiple meanings depending on whether they are interpreted in a religious or political context.
From here, one must also consider how the centrality of Roman religion to everyday Roman life affects the contemporary discussion of it, because this close connection between Roman religion and every other element of public and private life means that certain conventions and representations constitute an even larger complex of meanings, depending on their physical and social context. As discussed above, Roman religion was a necessary component of the empire's development, and understanding how the Roman religion served an important role in constructing Roman identity and culture allows one to subsequently appreciate how this religion might be encoded into not only explicitly religious texts, but also the physical objects and spaces used and inhabited by the Roman people.
Thus, one must understand "that temples, altars, sacred precincts and groves were more than just a 'backdrop' to religious ceremony, but were themselves (in their layout, design decoration) an important part of the religious experience, bearers of religious meaning" while at the same time serving some fairly utilitarian purposes."
In much the same way that Roman religion served to mark the boundaries of acceptable Roman identity, culture, and history, so too did the religious spaces of Rome form "part of a sacred topography" which seamlessly blended the social, political, and religious into the singular visual and spatial landscape of Rome itself.
For this study, which concerns itself with the Ara Pacis, or altar of peace, the forum of Augustus, and the grove of the Arval brothers, it will be important to note how these religious spaces simultaneously function as sites of political and social interaction as well, and most importantly, how this multidimensional function is exhibited in the physical record of these spaces through their layout, choice of visual and narrative details, as well as clear variety of structures and purposes.
The first physical, non-literary record of Roman religion to be considered here is the Ara Pacis, or altar of peace, constructed to honor emperor Augustus and featuring a number of friezes depicting real and mythological figures. The friezes depict a series of figures in procession, and wind around the outer walls housing the actual altar. On the southern side, one can identify "several members of the imperial family (including Augustus himself)," while the northern features "members of various priestly colleges."
Furthermore, just to the right of the steps leading up to the altar, there is a frieze depicting "Aeneas sacrificing a sow on his arrival in Italy."
Considering each of these elements in detail and in conjunction with each other will reveal not only something about how the altar functioned in the context of religious practice, but also its social and political role in the formation of Roman identity.
One may begin with the sculpture of Aeneas, if only because this image represents one of the oldest visual codes present in the Ara Pacis. The inclusion of Aeneas provides a link to "not only the mythical origins of Rome, but also the origins of the Roman ritual of sacrifice -- a ritual no doubt regularly performed at the Ara Pacis itself."
Almost immediately one can see the multifarious connections between Roman religion and identity, because the inclusion of Aeneas on the Ara Pacis provides a kind of mytho-historical justification for its existence by linking contemporary religious practice with Rome's history, both in terms of literal practice, such a sacrifice, and in the visual codes which inform this practice.
This is why Aeneas "wears a toga without a tunic, believed by the Romans to be the oldest form of Roman dress," and he is "sacrificing in Roman style -- that is, with head covered, in contrast to the Greek practice of sacrificing…