As of today, the Times of Chaos happened 15,000 years ago.
The Times of Chaos started when the Dark Council attacked the other gods, trying to become the only gods in existance.
The planes and worlds was in a constant state of war after this, only calming down after a hundred years or so. There was no longer any clerics as they had been, all divine power had disappeared as had the gods themselves. No divine power was channeled for nearly 3000 years after this.