The Dragon Kings were the first intelligent life in Creation.
Before the Primordial War, the ferocious and proud Dragon Kings were the masters of Creation. The gods created them to serve and worship them, just as the Primordials had made the gods to be their servitors. The Dragon Kings were made to be especially tough and durable, as Creation was newly formed and unstable, so that earthquakes, hurricanes, and volcanoes were all regular occurrences, and huge deadly predators roamed the land and swam in the seas.
At this point in time, Creation was barren of intelligent life. The gods lived on the Blessed Isle, while the Primordials lived in Yu-Shan. The gods created four breeds of Dragon Kings, one for each of the 4 directions of the Threshold. The Mosok for the islands and oceans of the West, the Pterok for the icy North, the Raptok populated the jungles and forests of the east, while the fierce and sturdy Anklok ruled the fiery South.
Being one of the first experiments at creating thinking beings with purely physical bodies, the Dragon Kings were spiritually halfway between gods and mortals. Their souls, though immortal and retained some memories of their past lives, their bodies were made of mortal flesh and lived between 300 and 350 years. When a Dragon King died, his spirit was reborn in an egg of another of his kind. The personality remained intact, but the process of rejoining a physical body stripped away most of the memories and power from his spirit, and thus Dragon Kings were reborn as savage beasts who required special training to regain their reason and memories. And even when both were regained, they were left with only fragmentary memories from their past lives.