In terms of Roman mythology, the god Jupiter is the king. In fact, he is often referred to as the king of the gods. He may not be the original creator of the MYTHOLOGICAL CREATURES that dominated tales and lore; that distinction belongs to his father Saturn. But Jupiter is the main man, a la ZEUS in Greek mythology.
Mythology dominated religious culture in Rome up until the point in which Christianity took over. Until that happened, Jupiter was the main deity. He was the god of the sky and, along with the help of the kings of the time, established principles of the Roman religion.
His similarities with Zeus and the GREEK MYTHS didn’t stop with their connections with the sky and thunderbolts. Jupiter was brother to two other gods: Neptune and Pluto. Like the Greeks, each of these three gods controlled one realm of existence: the sky (Jupiter), the sea (Neptune), and the underworld (Pluto), with Jupiter being the most powerful.
Rome’s Religious King…