The Fenright Tithe Wars was the name later given to an Imperial Crusade launched against the long burning civil wars that had riven the neighbouring Cal-Sek, Nepthis and Sadusyne Sectors. In their baptism of blood as a fully active Chapter, the Fire Angels Space Marines committed their full strength to the Third Imperial Interdiction force under the command of Lord Militant Helstrom in 760.M39.
The Fire Angels were deployed to the Heretic world of Jhoppa to break the deadlock between the Astra Militarum forces on that vital industrial planet and the massed ranks of the rebel "juggernaut" companies; the Heretics being supplied with large quantities of battle tanks and field artillery from Jhoppa's massive defence armouries.
The Fire Angels tipped the balance in a savage three-year-long campaign, matching their swift-moving Predators and Razorbacks against the rebel-crewed Leman Russ and Malcador tanks in open battle on Jhoppa's ash-plains, while their Tactical and Sternguard Squads wreaked untold havoc in close-quarter fighting in the tangles and treacherous terrain of the planet's extensive shatter zones.
Through a string of victories, the Fire Angels were instrumental in turning the tide of the war for Jhoppa and brought a world back into the Imperial fold that had lain in the hands of the Apostate for more than three Terran centuries. The Fire Angels remained active throughout the latter part of the Tithe Wars through 411.M40, and gained noteworthy victories contesting the Ork incursions into the Vorsk Sub-sector where they held out against a Speed Freek horde on Lambast's End, and struck deep into enemy-held territory to relieve the besieged Ecclesiarchy Shrine World of Lament.
It was this last action, fought against the nightmarishly powerful psyker-cult forces of the Seven Daughters of Oblivion and their mind-slaved followers, for which the Chapter was awarded the high honour of the Order of the Martyr's Heart by the Holy Synod of Gathalamor.
- Imperial Armour Volume Nine - The Badab War - Part One, pg. 92