During the 3rd century AD, when the Milesians - an independant group of enlightened - led by Merlin invaded Ireland, they unexpectedly managed to drive the Tuatha Dé Danann out of the World.

Armed with their tremendous success, Merlin decided to make of the Tuatha Dé an example for the other pantheons which had been waging wars against each other for decades, leading to the death of many Godborns, cultists, and other servants of the Gods. Merlin and his allies - mortals, Gods and mythborns alike - created a powerful ritual, the Concordat of Stonehenge, which used the nature of Otherworlds, intermediary realms between the World and Overworld, to enhance their role as a barrier between the two. The conclusion of the Concordat made it exceedingly difficult to enter the World by Legendary entities, requiring a strong Fatebinding between the World and the entity to do so. Since then, any Gods or Titans interested in the World had to do so through painstakingly-long setups of cults and mounting invasions, often spending most of that time hiding from both the Secret Societies and their Legendary rivals.

Since then, the number of Godborns increased dramatically since they became the main way for pantheons to win influence over the World. Nevertheless, because of the existence of the Concordat, Godborns who go out of bounds or are a threat to humanity in the World are quickly hunted down by Mythborns and Secret Societies.