Initium Gloriae

The Initium Gloria is the name of the Imperial campaign fought by the Argent Leviathans Space Marine Chapter against the infamous Flawless Host Chaos Warband when they invaded the home system of the Argent Leviathans' demesne and attacked their Chapter homeworld of Caerule. It was here, that the then-young Chapter suffered their first defeat at the hands of Chaos Warband. This defeat helped to deflate their notorious egos, humbling the Chapter, but not diminishing their desire the bring the wrath of the Emperor down upon the enemies of Mankind.

History
Established during the 25th 'Bastion' Founding in 712.M40, it is said that the Argent Leviathans were originally created in order to defend against a minor chaos incursion into the Segmentum Obscurus. After easily besting many small warbands the members of the Chapter began to become boastful and arrogant, a trait that still remains within the chapter to this day, because of this they would get cockier in battle leading to unnecessary casualties. After roughly 60 years of their egos growing due to never having lost a battle they deemed as a loss, the Chaos Warband, the Flawless Host, began to make their way to the Argent Leviathans homeworld, Caerule, it was here that the chapter have their first real fight and their first supposed defeat that crushed their inflated egos and forged a hatred deeper than the Great Ocean in the flames of battle.