With their successful defense of the Luk during the Battle of Tukayyid, the 91st Division is one of the most elite rated units in the Com Guards.
Immediately prior to the Clan Invasion, the veteran ranked 91st Division, then a omicron-based formation referred to by the nickname of Visions of Words, was assigned to the First Army, and was head-quartered on the Draconis Combine world of Pesht.
During the Battle of Tukayyid, the First Army was tasked with defeating Clan Ghost Bear. Along with the 12th Division, the Ninety-First trapped Delta Galaxy's 20th Polar Bear Attack Cluster in the outskirts of the Holth forest, inflicting heavy losses and turning the tide in Bears' push for Luk.
Unfortunately as the Ninety-First fell back to assist the 103rd Division in the defense of Spanac, they arrived on the city outskirts barely ahead of the OmniMechs of the Ghost Bears' Alpha Galaxy. Unable to establish a proper defense, the arrival of Beta and Delta Galaxies allowed the Clan forces to overrun the Ninety-First and capture most of its supply caches intact, forcing Precentor Martial Anastasius Focht to order the Hundred and Third to withdraw, ceding the target city to the Ghost Bears.
In an effort to tie-up the forces in Spanac, under massed artillery fire from the Fourth Army, the Ninety-First joined the Twelfth Division in raiding the outskirts in an unsuccessful attempt to take the city back prior to the declaration of the Ghost Bears draw.
Choosing the nickname of the The Luk-y 91st after their efforts on Tukayyid, the now elite ranked Ninety-First was rebuilt as a BattleMech heavy eta-based formation, remaining with the First Army but moving its headquarters to Dieron. In an effort to maintain their edge, the Ninety-First carried out numerous exercises against its own battalions and against.