Kritocracy-Ascendancy War

The Kritocracy-Ascendancy War was a conflict in the which saw the Exoi Kritocracy battle the  for dominance over their region of space. It lasted for less than a year, taking place entirely during 3,784 BBY, but saw massive casualties on many worlds before the Chiss finally prevailed.

Combatants
The Exoi Kritocracy had existed for 806 years by the time of the war, roughly seven hundred of them after developing spaceflight and expanding to worlds off its native Toriafas. It controlled 896 planets, many of them acquired by conquest. Its military was heavily mechanized, relying on s and Exoi battle armor for most of its conquests. The Exoi species controlled the highest levels of government, but some of the Kritocracy's alien citizens served as auxiliaries in the military and in lower government positions.

The was ruled by the  themselves, and consisted of the capital world  and twenty-eight Chiss colonies. However, the Ascendancy held sway over thousands of other systems with varying degrees of actual control. The was responsible for military force as a tool of statecraft, while  defended the Ascendancy's colony worlds.

Both the Exoi and the Chiss were expansionist, though in different ways. The Chiss exerted nominal control, largely in the form of "spheres of influence", over neighboring regions of the galaxy. The Ascendancy proper was only Csilla and the twenty-eight colony worlds, even when Chiss settled on other, more remote planets. The Exoi, by contrast, deliberately absorbed the worlds they conquered as full members of the Kritocracy.

The war
With both the Exoi and the Chiss spreading out and exploring, conflict was inevitable. Early battles saw devastation on both Kritocracy and Ascendancy-influenced worlds, with the Chiss Army trading blows with the Kritocracy's battle armor and war droids. The conflict was largely fought along the outer reaches of both areas; the single Kritocracy drive for the Ascendancy itself, the Battle of Kinoss, saw the Exoi suffer a defeat against the combined might of the CEDF and Kinoss's Colonial Phalanx.

Though they initially appeared evenly matched, the Chiss proved more adaptable than the Exoi, using starfighters to great effect to capitalize on the Kritocracy's weaker naval forces. The Chiss managed to repel the Kritocracy's forces, wreaking devastation on a number of military outposts. The Kritocracy attempted a resurgence, scoring a few victories to blunt the Chiss advance before suffering a brutal, conclusive defeat at the Battle of Sandrezhdredan.

Aftermath
Though a dominant power in its area of space, the Ascendancy had not yet evolved into the galactic powerhouse it would become in later millennia, and the need to preserve resources and deal with other threats in the Unknown Regions prevented the Chiss from pursuing the Exoi to total decimation. However, the Kritocracy lost control of hundreds of worlds in the war and its immediate aftermath, and the defeat started a four-millennia-long decline into obscurity. When the Kritocracy finally submitted to the Golden Empire and dissolved its government (ironically eighteen years after the Empire had conquered the Chiss Ascendancy), it had only nineteen worlds left.