The demon clan's sacred place was within the remote Demon Swamp. Legend had it that the Tree of the Flowing Bloodshed could absorb the tainted energy of the world and transform it into demon aura. It was held as sacred grounds by the powerful demon kings. Every new demon king would come here to absorb the demon aura and cultivate to obtain more power.
A long time ago, The demon god protected the Tree of the Flowing Bloodshed. The demon god was worshiped by all the demons, and even the powerful demon king was as subservient as an ant before it. Only after an elaborate kowtowing process would the demon king get the chance to cultivate in the Demon Swamp.
Following the destruction of the demon god, the Tree of the Flowing Bloodshed was no longer protected. All wanting a piece of that sacred territory, the demon kings fought each other and that place had become fragmented by all that internal rivalry.