During the Pax Romana, Rome expanded its rule into areas of the Mediterranean world where Greek culture already thrived. Greek city-states came under Roman control, as did vast territories conquered centuries earlier by Alexander the Great. As Roman rule spread, Greco-Roman culture created a bond between people separated by many miles.
In religious matters, Romans adopted Greek deities and gave them Roman names. So Zeus became Jupiter, Hera -> Juno, Poseidon -> Neptune, Hades -> Pluto, Athena -> Minerva,
Aphrodite -> Venus, Ares -> Mars, Artemis -> Diana, Demeter -> Ceres, Hermes -> Mercury, Hephaestus -> Vulcan, Hestia -> Vesta, Dionysus -> Bacchus. The only Greek god whose name didn’t change was Apollo.