After the Hyborian Age, the ancient Greek civilization began to rise, so Zeus made the Olympian gods known to them to gain their worship. Zeus discovered the principal nexus between the Olympian dimension and Greece was at the top of Greece's Mount Olympus, near Olympia, the principal city of Earth's Eternals. Zeus and his daughter Athena met with Zuras, the leader of the Eternals, and his daughter Azura. Given the physical resemblance between the Eternals and Olympians, both parties formed an alliance, with the Eternals representing the gods on Earth. Zuras soon decreed that Azura become Thena. However, the humans began to think of the Eternals as the Olympian gods themselves and not merely their representatives, leading to a growing resentment by the gods towards the Eternals which eventually erupted into war for a time. Christianity eventually became the dominant religion of the Roman Empire, and Zeus decided that the Olympian gods would break most of their ties with Earth, except for Poseidon, who would continue to watch over his worshippers in Atlantis. During the war of Troy Zeus battled Thor who had accidentally been transported there. Hades deplored Zeus' decree, and challenged Zeus' supremacy many times. A millennium ago, Hercules transported a band of soldiers from ancient Greece through time to battle Norsemen who were under the protection of the Asgardian god Thor, leading to war between the Asgardians and Olympians. Zeus met secretly with the Asgardian ruler Odin, and the two elder gods put an end to the war and formed an alliance to defend Earth from the Celestials.