The classical Greece of historical fame emerged around 750 B.C.E when the fiercely independent but similarly united civilizations flourished as one society. During this time these civilizations developed a belief system of gods, philosophy, and citizenship unique to other civilizations of the era. After the fall of the Greek empire, the Romans picked up the pieces and assimilated some of the greek ways of thinking into their own. This led to many connections between their belief systems. Rome and Greece had similar personalities and characteristics of gods and the way they worshipped said gods, yet they had disparities such as how states in Greece had a common belief in religion while Rome was somewhat a melting pot of different religions.
One connection Greek belief systems had with Roman belief systems is the parallels to each other’s gods. After Rome assimilated the Greek mythos into its own, it blended and slightly changed the gods of the Greeks to make their own gods. These gods, in turn, were very similar, both relating to things such as natural disasters, elements, personality traits, and values, only with changed names and mythos. Some evidence of such parallels is evident in roles played by gods such as Zeus and Jupiter, who both play protector to humankind and are the god of the sky and thunder. This evidence can be found in ancient Greek and Roman literature like the Iliad or the Aeneid.
Another way that Greek and Roman belief systems were similar was the way they honored their gods. Greeks would sacrifice animals before going on long voyages or competing in sports, and the Romans thought it was the best ways to communicate with the gods. Both would do it in religious temples such as the Pantheon, a place for worship of all Roman gods. Another way they equivalently worshipped is through festivals. Romans celebrated special days corresponding to their gods through festivals, which included possessions and parties, such as Equirria where people raced horses and Ludi Piscatorii a day dedicated to fishermen. Greeks also celebrated several special days like the Romans, like the all too familiar Olympics or new years. All of these similarities show that the assimilation of culture from Greek to Roman carried over sacrifice and festivities, proving they have similar ways of honoring their gods.
A difference in Greece and Roman belief systems was the number of different religions in the societies. Greek religion was polytheistic and was a uniting force in early Grecian societies.
And since greeks expansion was based on settlement rather than invasion, there was no need to introduce and support any new religions to keep their new territory. In contrast, when imperial Rome conquered and assimilated other societies, they brought with them their culture and religious ideology, which Rome had to include if they were going to keep the society from revolting. This led to a culturally diverse Rome, along with changes of the base religion in the region, something Greece never had. Changes in names of gods, changes in the gods entirely, or changes in the religion entirely, like when Emperor Constantine converted to Christianity and it became the main religion in Rome until it’s fall.
In the end, Grecian cultures continued through Roman traditions until it’s eventual downfall, but still spreading their cultures and beliefs. The belief systems of them both still prospered and evolved through the empires after them, such as their similar gods and the way they worshipped. Rome allowance of many cultures helped its culture stay alive during the invasion of Germanic tribes, and thanks to Rome’s support, several of its belief systems such as Christianity and Judaism, continued to prosper and spread from their hearths.