In the ancient Greek world, religion was personal, direct, and present in all areas of life. With formal rituals which included animal sacrifices and libations, myths to explain the origins of mankind and give the gods a human face, temples which dominated the urban landscape, city festivals and national sporting and artistic competitions, religion was never far from the mind of an ancient Greek. Whilst the individual may have made up their own mind on the degree of their religious belief and some may have been completely sceptical, certain fundamentals must have been sufficiently widespread in order for Greek government and society to function: the gods existed, they could influence human affairs, and they welcomed and responded to acts of piety and worship.
The religion of Ancient Greece was classified as polytheistic, which means that they believed in multiple deities. In fact, the gods and goddesses that we know as the Olympian Gods were something that many religious experts accept as being at the core of their belief system. Although there were multiple gods and goddesses that existed in Ancient Greece, these twelve represented the core of what most in Ancient Greece believed in. There are other gods and goddesses, however, that may also have been worshipped locally. The Twelve Olympian Gods and Goddesses include Zeus, Hera, Poseidon, Demeter, Athena, Apollo, Artemis, Ares, Aphrodite, Haphaestus, Hermes, Hestia, and Dionysius.