Story of the Seals

About 1000 years ago, a very evil elder god (so powerful that even to speak his name or think of him gives him power, whether one worships him or not) broke into the universe and tried to rule or destroy it. Other gods fought it back, and imprisoned it behind 7 Seals. Heironeous, Wee Jas and Ehlonna were the major gods involved in this. 7 Seals were created and carefully guarded. Currently, 4 of them are broken (resulting in, among other things, a plague of Chaos Beasts on the land. The party has been able to save one from being broken, and is looking to repair others that it knows of.

The events of 1000 years ago may be related to the raising of the great barrier mountains to the west, as well as the fact that even creatures that were alive then don't have good memories of exactly what happened back then.