The conflict was led by the Gods who hated their masters, but were forbidden from raising their hands to them. Therefore, aided by the renegade Autochthon they placed shards of their Essence into mortals and created the Exalted to fight on their behalf.
The war ended with the vast majority of the Primordials either dead or subjugated. Only four escape unharmed: Gaia, Autochthon, and two others. Of the two remaining, one was eliminated during the Aftershock War.
In the early history of Exalted, the Primordials ruled Creation from the celestial city of Yu-Shan and stayed in Heaven to play the Games of Divinity. The Gods were in turn delegated to the maintenance of Creation, administering reality from the Blessed Isle. In this era, the Celestial Incarna grew envious of their creators and desired to have the Games of Divinity for themselves. However, the Primordials had bound the Gods by powerful oaths during their creation, and the Gods could not attack or otherwise harm their makers directly.
Some incalculable time after the beginning of creation, the Unconquered Sun devised a plan for revolt. Making secret alliances with the Primordials Autochthon (always mistreated by the other Primordials), and Gaia (who had by this time abandoned Cytherea for a new lover, Luna), as well as selected Gods throughout creation. To the Gods he selected, the Unconquered Sun offered positions within the coming new order, and the ownership, rather than the stewardship, of reality.
The exact details of the Primordial War are unknown. What is known is that the foremost weapon of the Gods were the Exalted, created through a process given by Autochthon to the Unconquered Sun and used to create the Celestial Exalted and Terrestrial Exalted. The Exalted were armed by Autochthon as well, with powerful weapons that the Primordial had designed. The leadership of the war was under the control of the Unconquered Sun, but the tactics that won it were developed by the Maiden of Battles. The war ended with the death of several Primordials, who became the Neverborn, and the exile of the others, who became the Yozis. The dying curses of the Neverborn fueled the Great Curse, although its full impact would not be felt until the end of the First Age.
At the end of the war, with the vast majority of the Primordials either dead or subjugated. Only four escape unharmed: Gaia, Autochthon, and two others. Of the two remaining, one was eliminated during the Aftershock War.
The Exalted were promoted to guardians and stewards of Creation, taking this role over from the Gods. The Gods, in turn, retired to Yu-Shan. The highest Gods took play at the Games of Divinity, while the rest took new roles in the Celestial Bureaucracy, ultimately under the rule of the Unconquered Sun.
The older races, the Mountain Folk and Dragon Kings, slowly fell into obscurity through senescence or mystic oaths, and Autochthon fled Creation at the first inklings of the curse. The world entered the First Age of Man, and the seeds for the Usurpation were already sown.