The Iron Hounds is a Loyalist Space Marine Chapter and successor of the Ultramarines of unknown Founding. Renowned for their relentlessness, the Iron Hounds are ruthless warriors who pursue their enemies until every last foe has been slain.
Hailing from the world of Orinus in the Ultima Segmentum and with legends of their history dating back to the 4th Founding, the Iron Hounds have always been firm allies of the Ultramarines and have pledged warriors to the cause of Ultramar on countless occasions, most notably in the Plague Wars and at Damnos.
- Psychic Awakening - Assault on the Kebban Sub-sector (Unknown Date.M42) - The Iron Hounds despatched 2 companies to deal with the greenskins of the Kebban Sub-sector during the Psychic Awakening. The Kebban Sub-sector is a region of Imperial space that was infested with Orks and a horde of these xenos began to emerge from the sub-sector to assault the surrounding Imperial worlds. The Inquisition discovered that this WAAAGH! was set to collide with a different Ork horde led by the Warboss Bakrash, enhancing the potential destructive power of both. To prevent this from happening, the Ordo Xenos tasked the Deathwatch with killing Bakrash, but the operation ended in failure. This caused Bakrash to lead his WAAAGH! into the Kebban Sub-sector and make war upon the Orks already rampaging within it. Fearing that a Warlord would soon emerge to unite the Orks, the Ordo Xenos immediately requested the aid of several companies from the Rift Cobras, Templars of the Covenant and the Iron Hounds Chapters. The Ordo now believes that the forces of these Chapters will successfully destroy the Orks of this region while the xenos are still focussed on combating each other.
- Third War for Damnos (Unknown Date.M42) - The Third War for Damnos began when an invasion force of the Necron Szarekhan Dynasty descended upon Damnos during the Era Indomitus. The world sent out a plea for aid once more to the Ultramarines, who at that time were engaged in a number of major conflicts of the era, including the Indomitus Crusade, the Plague Wars and the War of Beasts. With most of their strength utilised elsewhere, the Chapter had few Astartes to spare to help the besieged world. Nonetheless, the Chapter had given too much previously in Damnos' defence to abandon it and a small strike force of Ultramarines and several regiments of the Ultramar Auxilia were sent to aid it. The Chapter knew that the forces that had been deployed to Damnos would be insufficient to defeat the Necrons and so requested aid from their allies in different Chapters. Their requests were answered and when the Ultramarines arrived at Damnos they were joined by contingents from several Successor Chapters, including the Iron Hounds, Brazen Consuls and Libators. The combined might of these Adeptus Astartes, however, was not enough to defeat the invading Szarekhan Dynasty, whose forces were numberless. This was due to the undying xenos arriving in their thousands by Tomb Ships and through a Dolmen Gate to ensure they reconquered Damnos. When the Mandeville Point for the Damnos System once again flared as it opened to the Warp, the Ultramarines feared that another foe was about to join conflict, but instead it marked the arrival of reinforcements sent by the Salamanders and White Scars Chapters. They had received the Ultramarines' request for aid and proceeded to join the battle to retake Damnos once more for the Emperor from the Szarekhan Dynasty.
- Plague Wars (ca. 012.M42) - The Iron Hounds deployed forces to aid the Ultramarines in defending the Realm of Ultramar from an assault by the Death Guard Traitor Legion and other servants of Nurgle.
- Assault on the Scourge Stars (Unknown Date.M42) - In the wake of the Plague Wars, the Iron Hounds were among the Imperial forces that sought to take the fight to the servants of Nurgle on the diseased worlds of his outpost in realspace, the star systems collectively known as the Scourge Stars. Imperial high command currently believes that the entire Iron Hounds Chapter may have been lost in the fighting on those worlds.
The Iron Hounds' Chapter badge is a black hound head with an iron collar centred on a field of white.
- Codex: Space Marines (9th Edition), pp. 10, 47, 58-59
- Psychic Awakening: Saga of the Beast, pg. 20
- Warhammer 40,000: Core Book (9th Edition), "War Zone: Scourge Stars", pg. 139