The Taiidan High Guard was an elite Taiidan Imperial Navy unit designated to protect and defend the Taiidan Emperor and the capital world of the Taiidan Empire. Comprising the first line of defense against enemy intrusion, hundreds of ships under the High Guard were assigned to secure the hyperspace inhibitor network surrounding the Hiigaran System. Ships that belonged to the Taiidan High Guard wore the all-black colour paintjob, contrary to the usual gold yellow and alizarin crimson red colour scheme of the Taiidan Empire.
The history of this formation goes back to 3000 BHL when the High Guard became the last line of Taiidani defense against the Hiigaran incursion. Sajuuk's Wrath in addition to the entire Hiigaran Navy hyperspaced behind the Taiidan defense formations to strike at the capital of the Taiidan Empire. The High Guard in its entirety engaged the aggressors, but did not stand a chance against this enormously powerful ship and its escorts. As a result, the Taiidan Imperial Palace was destroyed as well as all military facilities on Taiidan.
The Taiidan High Guard was also used to suppress rebellion. During the Battle of Vorshan's Rift, numerous vessels that had come under the command of the growing Taiidan Rebellion engaged with the fleets of the High Guard in a desperate bid to weaken the Emperor's stranglehold on the vast Imperial reaches of the Empire. The battle was a resounding victory for the Empire as the High Guard destroyed the majority of the attacking rebel forces.
During the Homeworld War, the High Guard was first encountered by the Kushan when Captain Elson, attempting to escape from pursuing Taiidan forces, stumbled onto the Exile fleet and requested assistance. Despite being a member of the High Guard, Captain Elson and a small number of Taiidani sympathizers decided to defect from the Taiidan Navy, due to the increased amount of corruption occurring within the Taiidan government.
The Taiidan High Guard was also assigned to guard the Hiigara System. This included Hiigara and the hyperspace inhibitor network. However, the Kushan knew the location of the most vulnerable station, thanks to the help of Captain Elson. After a lengthy battle, the Kushan managed to breach the defense of the station, capturing or destroying many Ion Cannon Frigates assigned to secure the station.
Several units of the Taiidan High Guard were sent to intercept the Kushan upon their arrival at Hiigara. In a last ditch effort, many such vessels were sent to attack the Kushan fleet and to defend the Emperor's flagship overseeing the battle from afar. However, several more formations of the High Guard had also defected to the rebellion and soon arrived in force to aid the Kushan under the command of Captain Elson. These vessels relieved the pressure on the besieged Mothership fleet and soon launched the spearhead of the final assault on the Taiidani Emperor, engaging many loyalist units along the way as they and the Kushan closed in. The Taiidan High Guard was soundly defeated by the combined Kushan-Rebel forces in orbit high above Hiigara and with such came the death of their Emperor soon after.