Gods in Ancient Greece and Rome

The religions of both the ancient Greeks and Romans were polytheistic (with many gods), but centered on a finite and homogenous group of deities who were worshipped through prayer, animal sacrifice, and festivals. It was believed that the gods, in turn, provided mortals with specific benefits, at the individual, family, group or state levels. Gods were anthropomorphic (in human form) and powerful but not eternal or all-powerful. New gods could be introduced into both pantheons (groups of gods), but the number of such additions was in fact fairly limited. And both Greeks and Romans concentrated on the cults of their traditional gods, whose worship they found both beneficial and satisfying for over one thousand years.