The Romans inherited an Indo-European pantheon, which manifested with considerable changes throughout the distribution of the various Indo-European languages. When Romans encountered pantheons that seemed familiar, they attempted to fit "those people's gods" into their Roman counterparts, taking them to be local manifestations of their own supernatural beings. Because the Greeks had such a rich literary tradition and they had gods that were easily recognizable as counterparts of the Roman tradition, the Roman's embraced that literature, but they did not "just copy the Greek mythology." They had their own traditions, which they freely augmented with literature that seemed to enhance their own beliefs. Romans wrote their own literature, sometimes in reaction to Greek writings, but Roman literature took on its own form, reflecting subtle differences in perception.

At times, the Roman attempt to fit foreign pantheons into their own failed. Belief systems mutate over time, and the amount of separation between the Germanic world, for example, and the Romans was considerable. Thus, the Romans believed that they recognized Mercury in the northern worship of Odin, but that was certainly a false fit since the Roman deity Mercury and the Germanic deity Odin (with all the various spellings for that entity) probably did not have a common origin. The fit with Greek gods was more easily achieved.

Unfortunately, much of what we know of Roman religion, traditions, stories, and ritual comes from Roman writings. This gives us a narrow view of what was really going on. We must also understand that Greek and Roman literature was written over many centuries. Traditions change, and we cannot view either as monolithic over time. Literature affected the process, sometimes slowing change, but as foreign influences were “digested,” change could accelerate.

At the same time, the vast majority of Roman citizens were not engaged with the literature of the time. They carried on their ritual practices and told their stories, immune to the direct effect of what anyone was writing – or what had been written - by Greeks or Romans. This “invisible” aspect of Roman religion can be addressed archaeologically and through hints in writing, but it is much more difficult to address. We can imagine, however, that this substrata of tradition was much less influenced by anything imported by the Greeks. The turbulence of waves and tides had little affect on those who lived at greater depths, but unfortunately, we can do little more than imagine what was going on at that level.