In ancient times, Cronos, son of Uranus and Gaia, had six children with Rhea. Four of them were swallowed by Cronos, while Zeus was spared and hidden from his father. As he grew older, Zeus forced Cronos to regurgitate the other gods. Alongside his siblings, they waged war against the Titans for control over the universe. The battle ended with Cronos and the eleven other Titans being sent to Tartarus.
In more recent times, in Greece, the Pope visited Athena's room after she was reborn as an infant. Before he could kill her, Saggitarius Aiolos intervened and exposed the Pope's true identity. Horrified by what had happened, Aiolos fled. The Pope declared him a traitor to the Sanctuary and ordered Capricorn Shura to murder him. This left Leo Aiolia feeling betrayed and resentful towards the Gold Saints and the entire Sanctuary.
The revival of the Titans marked the beginning of Aiolas story, as they sought vengeance against Zeus and the Sanctuary. This set off a battle between the Gold Saints and the Titans.