The command division known as Crimson Command was part of the Galactic Empire's Quelii Oversector. It initially served under the command of Warlord Zsinj. Following Endor, it effectively became the de facto flotilla of the Federated Teradoc Union, and subsequently the United Warlord Fleets. This flotilla was comprised of Imperial Victory-class Star Destroyers.
The name "Crimson" was given to the command because of the red-hulled Victory-class Star Destroyers, constructed from havod alloy, that made up its forces. The Star Destroyer 13X served as its flagship. The design philosophy behind the fleet favored a larger quantity of more agile, smaller vessels over a smaller quantity of slower, larger ones.
In recognition of his distinguished service, Grand Moff Zsinj of the Quelii Oversector was given control of the Crimson Command before 4 ABY. The fleet was incorporated into his Sector Fleet, which grew to become the largest fleet in the Empire, and Zsinj was promoted to High Admiral of Crimson Command.
After the demise of Warlord Zsinj, the fleet came under the control of the self-proclaimed "High Admiral" Treuten Teradoc, an Imperial warlord who had broken away from the Empire. Vice Admiral Gilad Pellaeon was the commanding officer of the flotilla in 12 ABY. At that point, it consisted of 73 Victory-class Star Destroyers, but 11 of them were destroyed during the Battle of Harrsk's fortress.
Following the unification of the Deep Core warlords by Admiral Daala, the unit's strength was increased to 112 warships. While not all of these vessels had red hulls, the name Crimson Command was retained. During a series of guerrilla raids against the New Republic, two of the ships were destroyed, both during the attack on the Chardaan Shipyards.
Colonel Ivan Cronus was tasked with taking twenty ships from the Crimson Command to assist Daala's assault on Yavin 4, while the remaining ships continued their guerrilla raids. Three Crimson Command ships, including the 13X, were destroyed in combat against a New Republic fleet during Daala's unsuccessful assault on the Jedi Praxeum, resulting in the deaths of Cronus and everyone else on board.