Gods and Demons
The Gods of Man
Writeups to follow. In brief, the gods worshiped in the Basin are the standard gods of the D&D 4e pantheon. Though referred to as the Gods of Man because they created the civilized races, some of them embraced the unchanged Primeval-spawned races in an effort to convert them for their own ends. This has met with varying levels of success. Only a few tribes of orcs venerate Gruumsh One-Eye above the Primevals, for example, but nearly all kobolds worship Tiamat.
The names of the Primordials themselves are mostly lost to time, imprisoned as they were millenia ago in the depths of the Elemental Chaos. Their children, though..
The avatars, exarchs and children of the Primordials, created to rule over the world in the dawn of history. Brought low and imprisoned with the might of ancient magic and the assistance of the gods. Like the Primordials, they could not be destroyed without destroying the world along with them, so instead they were imprisoned. Though not quite gods, they are beings of incredible power, and some of their influence still reaches the world through the visions of their shamans or the dreams of madmen.