Board Thread:Lore Discussion/@comment-5264386-20130125122221/@comment-2601:803:201:CC21:7026:D2AA:9360:E23E-20171107185327

The Occult was likely started by Havel who felt betrayed by his gods after Seath was granted dukedom and his archives and his questionable experiments.

Attach the Ringed City DLC and it really makes sense why after proving himself to Gwyn and his knights to be a mkst formidable human worshipper and warrior, he was disgusted that humans for there reward for service against the Dragons, were basically imprisoned on the edge of the earth and cursed. While Seath a dragon with traitorous blood, was made all but a Lord in his own right.