Was Jupiter simply the Roman name for Zeus?
Translation of divine names facilitated cultural comparison, but institutional roles, ceremonies and local religious histories cannot be collapsed into one set of myths.
First tradition
Greek Zeus appears in epic, sanctuaries and local cults. Panhellenic sites coexist with traditions specific to different Greek-speaking communities.
Second tradition
Roman Jupiter Optimus Maximus occupied a central place in state religion and was tied to oaths, public authority and Roman civic life.
How to compare responsibly
Separate mythic comparisons from actual sanctuaries, ritual calendars and inscriptions in each society.