The Chiss Expansionary Defense Force (CEDF), also known by alternative names such as the Chiss Expeditionary Defense Force, the Chiss Expeditionary Defense Fleet, the Chiss Expansionary Defense Fleet, or simply the Chiss Defense Force, functioned as the primary military arm of the Chiss Ascendancy. This organization was established by syndic Jer'Jo Cam'Co of ancient times, following the initial discovery of several worlds rich in resources during the early exploratory phases of the Chiss' history.
The CEDF was structured into two separate branches: the Expansionary Fleet, responsible for conducting patrols along the frontier and performing exploratory missions in the regions surrounding the Ascendancy, and the Defense Fleet, tasked with defending against hostile intrusions and addressing long-term strategic considerations. It is worth noting that when interacting with individuals from outside the Chiss Ascendancy, members of both the Defense Fleet and the Expansionary Fleet would identify their units by the complete designation of the Chiss military: the Expansionary Defense Fleet. It was also recognized that the Expansionary Defense Fleet included a reconnaissance division.
The CEDF played a role in Chiss political decision-making, providing a decisive vote when the Ruling Families reached a stalemate on how to proceed during specific events.
CEDF officers typically wore black uniforms, adorned with patches indicating their affiliation with specific houses, while members of the Hierarchy were distinguished by wearing entirely white uniforms.
The fleet utilized starfighter carriers, armored personnel carriers, heavy gunboats, and assault cruisers. The force also deployed Chiss Star Destroyers and AirStraekers. Subsequently, they incorporated Nssis-class Clawcraft into their arsenal, inheriting them from the Empire of the Hand. Transport vehicles included drop ships and assault shuttles.
Chiss commandos wore camouflaged, color-shifting fractal-pattern armor that gave them the ability to move across battlefields undetected. They were equipped with demolition satchels and charric guns. These commandos were deployed on specialized missions, such as placing vape charges on designated targets. Other types of soldiers included sharpshooters, pilots, and general soldiers.
The military also employed superweapons, such as the biological doomsday weapon known as the parasite bomb. They also used radiation bombs. The Chiss Defoliator was also developed.
During the era of the Cold War, Ath'en'terro served as a member of the CEDF.
Beyond this, there is limited documentation of the CEDF until around the time of the Yuuzhan Vong War. Even then, the Chiss forces most prominently involved were not standard CEDF units. The consular ship Chaf Envoy, which participated in the recovery of Outbound Flight in 22 ABY, was technically under the command of the Chaf family. Furthermore, the Clawcraft that were deployed alongside New Republic forces from 26 ABY onward belonged to Syndic Mitth'raw'nuruodo's Household Phalanx, which had evolved under the patronage of the Empire of the Hand.
Around 29 ABY, significant, and still somewhat mysterious, changes occurred within the CEDF and Chiss society as a whole. Imperial General Soontir Fel, a Human, reportedly led forces from Thrawn's Household Phalanx to intervene in a disagreement among the Ruling Families. As a consequence, he was appointed as the CEDF's Assistant Syndic, while another Human, Peita Aabe, was designated as Chief Navigator.
By 35 ABY, tensions along the frontier between the Chiss and the neighboring Killik Colony were escalating, leading to the first skirmishes of the Swarm War. It was during this conflict that CEDF forces were first observed operating on a large scale by external parties. The most substantial concentration of force observed during the war involved the deployment of nearly fifty Chiss Star Destroyers, along with hundreds of smaller capital ships, during the assault on Tenupe in 36 ABY.