Long ago, the whole world worshipped and adored the ancient gods. They were ruled by the Titan Kronos. Zeus and his brothers however defeated their father which led to chaos among the gods. When Kronos was king, he showed absolute ruthlesness so no one could challenge him. But as Zeus brought the new form of kingship there was rebellion. In other to build an army to stop his father's cruelty, he formed an alliance with the Norse god king Odin.
But after the battle, Odin decided that he should be king instead of Zeus. But the Greek gods refused so he instilled to breaking free from the alliance. Many gods followed him and soon Zeus lost most of his kingdoms.
With no other choices, he chose to give them a choice of peace or war. He contacted the two children he was most scared of. Athena, the goddess of wisdom and Ares, the god of war were summoned by Zeus. As Zeus explained the situation at hand, Athena came with a plan to go around the world and settle the disputes but if they refused Ares was to prepare for war.
Athena went throughout the world solving the disputes while those who refused were put to war with Ares.
Just as Ares syarted planning his attack on Asguard, the dwelling place of Odin, he received word that his father had called off the attack.
Zeus had sent a messenger to tell him that there would be no more bloodshed. This infuriated Ares who had already planned to battle Thor, god of thunder.