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|This article is about the Space Marine Chapter, for the Titan Legion see Imperial Fists (Titan Legion)|
The Imperial Fists were the VII Legion of the original twenty Space Marine Legions. Their Primarch is Rogal Dorn. The Legion remained loyal during the Horus Heresy, after which it was reorganised according to the Codex Astartes and divided into Chapters. The Imperial Fists have maintained an intense rivalry with the Iron Warriors since prior to the Horus Heresy, with whom they share a specialisation in siege warfare. The Imperial Fists are recognised to be among the most loyal Chapters to the Emperor and have been instrumental in holding the Imperium together during the bleakest of times with renowned stubborn resilience.[16a] Because of their service to the Imperium, especially their role in leading the defense of Terra during the Horus Heresy, the Imperial Fists are also known as the "Defenders of Terra." 
|Marine||Basic Data||Chapter Symbol|
- 1 Founding
- 2 The Unification Wars
- 3 The Great Crusade
- 4 The Horus Heresy
- 5 Horus Heresy Aftermath
- 6 Notable Events
- 7 Geneseed
- 8 Current Overview
- 9 Successors
- 10 Noted Elements of the Imperial Fists
- 11 Related Articles
- 12 Sources
The Imperial Fists were formed on Terra as the VIIth Legion. The Legion was one of the few that recruited entirely from their homeworld and were the only formation to have recruited from across all of Terra, including areas where other Legions claimed exclusive "Rights of Tithe." Despite recruiting from such a wide range of locations, VII Legion recruits consistently possessed a taciturn nature and were quick to action but reserved in speaking . The Legion had the benefit of being united with their Primarch shortly after their formation, while their character had yet to take fully shape and as much as 70% of their ranks were still aspirants. As result, the Imperial Fists and Rogal Dorn developed as servants of the Imperium together, forming an unbreakable bond based upon the common desires for self-discipline and total commitment to order found in Dorn's temperament and the gene-seed of the Legion.[2a]
The homeworld of the Imperial Fists is still officially given as Holy Terra.[16f] However, in functional terms, the Chapter has been fleet-based since being united with their Primarch Rogal Dorn, after which the massive starship Phalanx has served as their mobile Fortress-Monastery.[2e] Nonetheless, the Chapter still maintains a presence on Holy Terra, including the Pillar of Bone and Column of Glory. Prior to relocating to Terra, the Imperial Fists homeworld was Inwit, where Rogal Dorn was raised and where the Legion took many of their aspirants and starships from.[39a][39b] The Chapter still emphasizes its historic role as the defenders of Terra and maintains a coded sequence of alerts and signals to coordinate the rapid redeployment of its full forces to reinforce Terra against attack if the contingency arises.
The Unification Wars
The Imperial Fists participated extensively in the Unification Wars, and are noted to have taken the Cities of the Crystal Sea, conquered the Fortress of the Fifth Circle, and defeated the Wind Caller Clans in the Himalazia at the expense of losing three battalions. During this time, the The Legion earned its first battle honour, 'Roma.' In their first decade of existence, they raised six hundred citadels on Terra. Veterans of the Unification Wars commonly displayed the campaign's badge on their power armor. 
The Great Crusade
During the Great Crusade, Imperial Fists behaved as crusaders and were driven to conquest. First Captain Sigismund was a prominent voice of crusade ideology, believing that the Great Crusade was an expression of man's infinite desire to master space and that maintaining the Imperium would require perpetual war. The Legion espoused a philosophy of victory that held, "Victory was not enough, to conquer one had not only to defeat one's enemies, but to to hold the fruits of that victory." According to this view, victory therefore required consolidating power over the conquered society after the conclusion of combat operations, usually by way of building fortresses and military installations to compel a compliant social order. As a result, the Imperial Fists were considered to be “the most direct expression of the Emperor’s design of uniting humanity" and were generally regarded to be the "foundation rocks" on which the Imperium was built.
In their capacity as crusaders, the Legion emphasized their military role in the Great Crusade and eschewed the civil responsibilities of governing worlds for recruitment and other purposes. Dorn is famously recorded as saying "I want recruits not vassals." After being granted recruitment rights on Necromunda following a major victory against the Orks, the Legion situated itself as guests rather than masters. This attitude contrasted with the approach of other Primarchs, such as Perturabo of the Iron Warriors, who took every opportunity to garrison worlds, claim their tithes and develop a personal empire.[2a]
During the Great Crusade, the Imperial Fists demonstrated a stern disposition, even in comparison to other Space Marines. Upon first encountering the Imperial Fists, Captain Garro of the Death Guard remarked that "they seem a somber lot," to which Captain Iacton Qruze of the Luna Wolves responded in the affirmative, adding that he had served with a Veteran Imperial Fist for a year-long campaign who never once smiled. The stern character of the Legion earned the Imperial Fists the nick name "the Stone Men."
Doctrine and Organization
During the Great Crusade, the Imperial Fists were employed as a strategic reserve to reinforce fledgling campaigns or to achieve breakthroughs. The Legion rapidly redeployed between battlefields and developed special expertise in siege warfare and mass shock assaults. Offensively, the Imperial Fists employed assault formations, surgically applying force where and when it was required to shatter enemy defenses, often deciding the outcome of campaigns. Defensively, the Legion was commonly tasked to defend strategic positions and defeat enemy breakthroughs.[2a] [2d] Regarding the Legion's prowess in defending sieges, Horus once remarked to Dorn that "if I ever laid assault to a bastion possessed by you... then the war would last for all eternity, the best in attack matched by the best in defence." The Legion also possessed special skills in urban warfare and space operations, including fleet and void warfare.[2a] 
The Legion was organized to support its crusade posture. The Imperial Fists maintained a fleet of 1,500 warships, a force quantitatively and qualitatively superior to any other legion. The Legion command and control structure featured theater marshals in charge of all forces taking part in their area of responsibility, fleet masters, and siege masters. Ad hoc commands of castellan and seneschals controlled formations called crusades or households, respectively -- each comprised of two battalions. Infantry unit configuration tended towards the two extremes of assault load outs or long-range heavy weapons. To replenish combat losses, the Legion often recruited from conquered populations en mass. Recorded examples include recruiting every man who could carry a spear from the hunter-tribesmen of Tiberna, taking half of the members of the tech-brat gangs of Sevan, and the recruitment of every youth older than 10,000 ship cycles from the Nedoran ship clans.
The size of the Legion was recorded as 98,356 just prior to the outbreak of the Horus Heresy, though this figure is not thought to be precise.
Campaigns and Actions
The Legion was instrumental in extending control over the Sol System in the early phases of the Great Crusade, performing key roles in the Unheard War, the War of the Consus Drift, and the Araneus Wars. During the Unheard war, the Emperor ordered the Bell of Lost Souls tolled for the first time in honor of 50 Imperial Fists who sacrificed themselves to defeat a psy-plague in the Azurite Stations. On the Plains of Kenneatar, the Legion's 5th Battalion broke the lines of the Tyrancy with an arrowhead formation of 50 war machines. The Imperial Fists are noted to have conquered Galabaz, a subterranean city buried in surrounding mountains. During operations on Ophelia VII, 10,000 Imperial Fists accompanied the Emperor and 100 custodes. At Askanisa, the Imperial Fists and the Luna Wolves formed the Emperor's vanguard to break the Shrouded Dynasties.
The Imperial Fists were so effective in their role during the Great Crusade that the Legion accumulated a record second only to that of the Luna Wolves. As a proud testament to their accomplishments, battle honours were displayed for kilometres in a gallery aboard the Phalanx. However, in the course of accumulating honours, the Imperial Fists' developed hostile relationships with other Legions. Most notably, the Imperial Fists maintained a bitter rivalry with the Iron Warriors, which was largely the result of both Legions sharing similar combat specializations. Less known was the strong mutual hatred between the Imperial Fists and Alpha Legion, who clashed on more than one occasion prior to the Horus Heresy, though the nature of these clashes is unknown.
The Imperial Fists operated closely alongside the Emperor of Mankind during the Great Crusade. The Legion served as the Emperor's personal Praetorians and fought directly alongside him more than any other legion. The Emperor bestowed the name "Imperial Fists" upon the VII Legion early in the Great Crusade, a reference to when many saw the lands conquered by them it was as if "the hand of the Emperor had descended and gripped with an unbreakable fist." The Emperor also granted them the right to wear the Laurels of Victory as part of their heraldry. After the successful conclusion of the Ullanor Crusade, the Emperor returned to Terra, ordering the Imperial Fists with him where they were tasked to fortify the Imperial Palace.
The Horus Heresy
Rogal Dorn and the Imperial Fists were the first loyalists to learn of the Horus Heresy other than those attacked on Isstvan III. While attempting to reach Terra as ordered by the Emperor after Ullanor, the Legion responded to a distress call from the Eisenstein. Rogal Dorn discovered Death Guard Captain Nathaniel Garro and remembrancer Mersadie Oliton, who carried news of the events which had transpired on Isstvan III. In response, Dorn ordered the bulk of the Imperial Fists to the Isstvaan system while he and the Legion’s veteran companies returned to Terra to inform the Emperor of Horus' treachery. Significantly, each deployment faced difficulties from the Warp Storms that had enveloped the galaxy, which made navigation nearly impossible. 
On Terra, Dorn assumed command of the Imperium’s armed forces.[12a, 14a] There, the Imperial Fists oversaw the fortification of the Imperial Palace, as previously ordered before the Heresy, and other duties relating to its defense, such as counter-intelligence.
Dorn immediately organised the Imperium’s response to Isstvan III. After making contact as best as possible with the other Legions, which the Warp storms hampered, Dorn ordered that Horus be confronted on Isstvan V where his forces were entrenching themselves. Discussing the reasoning of this strategy with Malcador The Sigillite, he stated that “...kill the head and the body will die.” Notably, Dorn elected to keep his veteran companies on Terra while apparently assuming the bulk of the Legion which had been ordered to the Isstvan system would join the assault on their own initiative if they were able to navigate there successfully.[14a]
At the same time, Mars entered into open revolt, endangering the Imperium’s access to war material. In response, Dorn ordered First Captain Sigismund and Captain Camba-Diaz to command four veteran companies to secure the forges of Mondus Occulum and Mondus Gamma, which together produced the majority of Astartes weapons and armour.[14a] The Astartes force was accompanied by number of Imperial Army units, including thirteen companies of Saturnine Hoplites and four regiments of Jovian Grenadiers, also under the command of the Imperial Fists captains.[14c] The operation was met with overwhelming resistance by traitor forces belonging to the Adeptus Mechanicus. The two companies under the command of Comba-Diaz were outnumbered one hundred to one and Sigismund’s force of the same size was met by two full Titan Legions. Facing annihilation, the Imperial Fists withdrew from Mars, abandoning the forges but successfully evacuating at least 12,000 suits of MK4 Power Armour and twice as many weapons.[14b] The four veteran companies involved in the operation suffered heavy casualties and were reduced to half strength.[12b]
Months later, the bulk of the Imperial Fists forces were continuing their attempt to overcome the warp storms and navigate to the Isstvan system as ordered. The force had been completely out of contact with the Imperium since their departure and was unaware of any further developments concerning Horus' treachery, including that the remaining loyalists on Isstvan III had been crushed uterly. The fleet regained communication with the Imperium when it received urgent orders to return to Terra while being engaged by a large Iron Warriors force during the Battle at the Phall system. Both sides suffered serious losses but in a testament to their discipline the Imperial Fists fleet successfully disengaged and set course for Terra as ordered.[12c]
Defence of Terra
Horus Heresy Aftermath
Rogal Dorn's grief was immense in the aftermath of the Horus Heresy. Until that point, Dorn had been true, noble and enduring, but now he became an avenging son dressed in the black of mourning. Whereas other Legions, such as the Ultramarines, dedicated themselves to rebuilding the Imperium, the Imperial Fists launched a crusade against the Traitor Legions, hunting them down and levelling fortress after fortress. Yet the Legion was still cognisant of its broader role as it lent itself to direct calls for assistance by Imperial worlds and institutions more so than other Legions during this period. Nonetheless, Dorn was absent from the highest councils of the Imperium until he returned to Terra upon being summoned by Roboute Guilliman to be presented with the Codex Astartes.[2c]
Codex Astartes Crisis
Dorn initially rejected the Codex Astartes and enmity developed between him and Guilliman. Dorn called Guilliman a coward, citing his lack of participation in the defense of the Imperial Palace. Guilliman accused Dorn of being a traitor for refusing the Codex. This enmity quickly involved other Space Marine Legions and a rift developed, Leman Russ of the Space Wolves stood by the Imperial Fists, while Jaghatai Khan of the White Scars and Corax of the Raven Guard supported the Ultramarines. A second civil war appeared likely when the Imperial Fists strike cruiser Terrible Angel was fired upon by the Imperial Navy in connection with Codex crisis.[15a] However, Dorn ultimately relented after spending seven days meditating in the pain glove. There, he concluded that the Legion could no longer serve the Emperor who had been and must serve the Emperor who was, which involved accepting the new order of which the Codex was a part.[2c]
The Iron Cage
It was Dorn's decision that the Legion would symbolically enter into the pain glove together and emerge according to the Codex Astartes. This opportunity presented itself in the battle that became known as The Iron Cage. The Imperial Fists had largely dismantled the Iron Warriors empire in their campaigns immediately after the Heresy. Upon discovering the Eternal Fortress, a twenty square mile fortress constructed by the Iron Warriors, Dorn, fuelled by his enmity towards Perturabo, committed the entire Legion to its assault.[2c]
Perturabo and his Legion were masters of defence and siege in their own rite and had designed the Eternal Fortress as a trap to ensnare the Imperial Fists. Ceding further advantage to the Iron Warriors, Dorn led the assault without his customary care in planning and preparation. What ensued was a near massacre. The Imperial Fists’ formations were broken, reduced to fighting with combat knives battle-brother by battle-brother in half flooded trenches with their ammunition expended.[2c]
Yet, the Imperial Fists endured and the Iron Warriors were unable to finish them, lacking the faith to make the ultimate sacrifice that victory demanded. The Ultramarines then intervened, driving off the traitors.[2c]
Cleansed by their sacrifice at the Iron Cage, the Imperial Fists immediately began their reorganisation[2c] with the fully hardened, veteran force that remained.[2d] For the next two decades, the newly formed Chapter went into retreat in order to master the tenets of the Codex Astartes. The Chapter has since assumed a place alongside the Ultramarines as exemplars of the Codex.[2c] As part of their reorganisation, the Imperial Fists participated in the Second Founding, christening the Soul Drinkers, Black Templars, and Crimson Fists. The Legion’s most fanatical battle-brothers composed the Black Templars while the more level headed members founded the Crimson Fists.[2d]
- M30: Imperial Fists play decisive roles in campaigns during the Great Crusade, including the Unheard War, the Araneus Wars, and the War of the Consus Drift.
- 546.M32: In what became known as the Beheading, the High Lords of Terra are all slain on the orders of Drakan Vangorich, Grand Master of the Officio Assassinorum. The rogue Master of Assassins is tracked down and slain by a Space Marine strike force drawn from the Imperial Fists, Halo Brethren and Sable Swords. Only a single Space Marine survives the campaign.
- 378.M36: At the height of the Age of Apostasy, the Imperial Fists under Chapter Master Lazerian alongside the Black Templars, Soul Drinkers, Fire Hawks and forces of the Adeptus Mechanicus assault the Ecclesiarchal Palace on Terra, seat of Goge Vandire and his attempt to assume control of the Imperium.[15b]
- 654.M37: Fall of the Adamantium City
- 766.M37: The Dawn Hammer. Strike Force Ultra of the Imperial Fists destroyed the space hulk of the Ork Warboss Sunspitta.
- 755.M438 : During the the Siege of Balle Alpha, the Imperial Fists defend a capitol city against an Ork Waaagh! lead by warboss Gogard, inflicting heavy casualties and holding the city until reinforced by the Blood Angels. Tactical outlays remain of the defensive positions employed against an enemy armoured attack.[9b]
- 567.M40: Chaos-inspired insurgence on the planet of Iduno is pacified. The Campaign included the Battle of Colonial Bridge which resulted in the promotion of Darnath Lysander.[17a]
- 659.M40: During the Siege of Haddrake Tor, a three year long campaign recovers the world Haddrake Tor from Chaos, 1st Company Captain Kleitus is lost but passes the Fist of Dorn to Lysander before his death and with it the 1st Captainship.[17a] 
- 777.M41: The Battle of the Iron Labyrinth
- 790.M41: The Chapter takes part in the Nimbosa Crusade alongside the Black Templars and reclaim Nimbosa from the Tau Empire. Heavy casualties are incurred at the battle of Koloth Gorge.[6b]
- 830.M41: Chapter Master Vladimir Pugh leads two-thirds of the Chapter to retake a string of worlds in the Tyros Gulf that were conquered by Rogal Dorn during the Great Crusade but subsequently lost. The Imperial Fists are ambushed by Illic Nightspear and Eldar from Craftworld Alaitoc and Pugh is nearly killed but the campaign ends in success. 
- 853.M41: Alpha Legion forces intervene in the Krandor Rebellion, prompting the Imperial Fists, Fire Lords and Revilers to respond. The Space Marine forces successfully evacuate important artefacts before exterminatus is enacted. 
- 955.M41: 4th and 9th Company's lay siege to the Ork mega-stronghold named Fort Mork. The Imperial Fists are badly outnumbered but face down three days of Orks hurling themselves at their siege lines, defeating the xenos with precision bolter fire and a dozen thunderfire cannons. 
- 959.M41: During the Purging of Ganymede, the third company and at least one Land Raider Crusader conducted a campaign against the Contagion of Ganymede, the records of which have since been censored. [9a] [9c]
- 966.M41: Lysander leads the Imperial Fists to Malodrax and scours the Iron Warriors from the planet.[16c]
- 968.M41: 5th and 9th Companies are deployed to Khai-Zhan to suppress the Khai-Zhan Uprising alongside four Cadian Imperial Guard Regiments. The Imperial Fists force is decisive in countering the Night Lords taking part in the uprising and lays siege to the heavily fortified citadel the Palace of Peace.
- 969.M41 - The Invasion of Taladorn. Lysander leads Imperial Fists alongside Ultramarines and Blood Angels against Shon'tu's Sons of the Forge on Taladorn. Lysander's recklessness result in the near-total destruction of the 3rd Company and he is censured as a result.
- 970.M41 - As part of his censure for Taladorn, Lysander is temporarily stripped of the First Captaincy and assigned to 3rd Company, which he is ordered to rebuild. As part of this penance, Lysander is ordered to undertake the Crusade of Thunder against the Orks. Following the Campaign, Tor Garadon is promoted to 3rd Captain and Lysander returns to First Captain. 
- 970.M41 - The Infestation on Drashin. Chapter Master Vladimir Pugh is slain battling Tyranids, and Vorn Hagan assumes leadership of the Chapter after Lysander refuses the honor.[41a]
- 971.M41 - The Fall of Malodrax. Most of the Imperial Fists, led by the Phalanx itself, battles Warsmith Shon'tu at Malodrax.[41a]
- 975.M41: 2nd Company and Grey Knights under the command of Brother-Captain Arvann Stern cleanse Ghallamore of Skulltaker and his daemonic hordes. 
- 975.M41: The 3rd Company is dispatched by Vorn Hagan to reclaim 18 worlds along the Eye of Terror which have risen up in heresy. After the battle the Imperial Fists become so impressed with the Cadian allies that they begin to train some.
- 981.M41: Captain Taelos undertakes a warrior pilgrimage, taking him to the worlds of Maelstrom, Choria, Fell Heart and Golgotha.[17b]
- 984.M41: The Crusade of Valorous Steel. The Imperial Fists defend Pharos from Dark Eldar raiders.
- 988.M41: The Campaign of Fire and Steel. The 3rd Company and the Salamanders break the Alpha Legion hold on Magnas Prime
- 997.M41: The Defence of Miral II. A battle group led by Captain Lysander intercepts Hive Fleet Leviathan on the planet of Miral where defensive fortifications are established. Although severely outnumbered, the battle group drives off the Tyranid swarm on the seventh day, one day after the defence was expected to fail.[17c]
- 998.M41: 2nd Company engages outlying elements of Waaagh! Dethzarka. 6th and 9th companies dispatched in support.[16b]
- 998.M41: The Battle for the Endeavour of Will. The Star Fort Endeavour of Will is attacked by an Iron Warriors Warband. Enemy commander is believed to be the infamous Warsmith Shon’tu.[16b]
- 999.M41: 3rd Company is lured into a trap on the surface of Hydra Cordatus by the Iron Warriors and is nearly destroyed in the ensuing Siege. No more than thirty Battle-Brothers survive.[27a]  Captain Tor Garadon, now Captain of the 2nd Company, is tasked to rebuild the 3rd Company once more just as Lysander had decades earlier. He is aided by those veterans who fought alongside him during the 3rd Company's Crusade of Thunder that was instrumental to its last reconstitution. 
- 999.M41: At least five companies take part defending against the 13th Black Crusade, smashing into traitor Astartes at Cadia. The 1st, 2nd, and elements of the 3rd companies are instrumental in defending strategic locations on Cadia and 2nd Company wins battle honours for defeating a horde of mutants numbering 10,000. 
- 999.M41: The Battle of the Phalanx. At present, the 3rd Company is defending Phalanx from a Daemonic boarding action led by Iron Warriors Warsmith Shon'tu and the Daemon Be'lakor. Shon'tu and Be'lakor are seeking to outdo Abaddon's 13th Black Crusade by infesting the massive starship while on station in the Sol System and using it to bombard the Imperial Palace. Captain Tor Garadon is commanding 3rd Company's defense of Phalanx. His forces have inflicted extreme casualties on the attackers and maneuvered Phalanx into the warp in order to protect Holy Terra should they fail in repelling the assault. The Legion of the Damned have arrived to assist Garadon's forces as the battle grows desperate. The batting is continuing at present with no certain outcome. 
- Crusade of Fire: A major Imperial Crusade launched in M41 to reclaim the worlds of the Corvus Sub-sector.
- The Tunis Action: The planet Tunis is attacked by the Evil Sunz Orks and issues a distress call. Scouts from the 10th Company are first to respond, followed by 1st company, defeating the Ork force.
- The Conquest of Uttu Prime: The Imperial Fists battle the Necron Overlord Zahndrekh for control of Uttu Prime.
- The Scouring of Vernalis: Task Force Gauntlet liberates the planet of Vernalis from Chaos. The Task Force is composed of elements of the 10th, 5th, and 1st companies and defeats a warband of Roaring Blades and Emperor's Children under the command of Arch Traitor Sybaris.[6c]
- Battle of Mithron: The Imperial Fists 5th Company is destroyed defending the shrine world of Mithron, home to the sacred Liber Mithros, from Chaos daemons and Black Legion Chaos Space Marines. However, two survivors manage to keep the artifact secure and are rescued by a force of Ultramarines.
- The Jorgurd Cluster: The Alpha Legion inspired rebellion at Klebendor III is crushed and the heretic's leader Ialo Vex and his inner circle are captured. The Alpha Legion forces are pursued to a remote base hidden in the asteroid belt at the Rathnorn system where they are destroyed.
- Battle of Naeuysk Gorge: Fourteen Rhinos are lost to a Night Lords Ambush. The Imperial Fists counter-attack the following morning, successfully pushing back the Chaos Space Marines and reclaim the lost vehicles. A casualty rate of nearly 85% is incurred.
- Ironstar of Yorg: Captain Lysander and his Strike Force Ultra recaptured the Ramilles Class Star-fort from the Iron Warriors.
The Imperial Fists gene-seed possesses two unique characteristics that are expressed in physiological and the behavioral terms. Physiologically, the Chapter has lost two of the organs particular to Space Marines: the Betcher's Gland, which allows the Marine to produce acidic spittle, and the Sus-an Membrane, which allows the Marine to enter a state of suspended animation.[3a] Behaviorally, the Imperial Fists are given to an obsession with conquering pain by force of will and discipline.[3a] The Chapter's obsession with will power and discipline is sometimes characterized as further involving a deep-seated drive towards self-sacrifice or penance.  This trait is often simplified as merely involving a stubborn disposition.[16a]
The Chapter considers the behavioral characteristics of its geneseed to be both a strength and a weakness. On the one hand, such tendencies engender stubborn conduct on the battlefield and ensure battle-brothers are more likely to fight on despite terrible injuries. On the other hand, Imperial Fists may subconsciously invite such injuries and difficulty, which can imperil battle planning and lead to unnecessary risks of personnel and material. Along these lines, the Imperial Fists are noted to be reluctant to accept the possibility of defeat when retreating would be the wisest course of action. The Chapter consciously attempts to minimize the liabilities of these behavioral traits while maximizing the benefits. [3a]
Doctrine and Organization
The Chapter retains its previous special ability in siege warfare, urban warfare and defense, although aggressive rather than defensive operations are preferred. [2d] The martial reputation of the Chapter has focused primarily on siege warfare, "The Imperial Fists are renowned siege masters par-excellence." The Chapter is noted for both "grimly defending fortifications against innumerable foes, or storming valiantly against bastions."  The Imperial Fists also place great value in marksmanship and are renown for their accuracy with ranged weapons, especially boltguns. Battle-brothers spend a disproportionate amount of time in Devastator Companies in order to perfect the art of the long-range kill.  While a practitioner of the Codex Astartes, the Chapter also maintains its own martial tradition as codified in the Book of Five Spheres as an addendum to the Codex Astartes.
The force structure of the Imperial Fists supports its predilection for siege warfare and high risk operations. The Chapter maintains more siege-related weaponry than any other Chapter, including a small army of thunderfire cannons.  The Chapter also maintains a reserve of initiates far deeper than any other Chapter to replace its combat losses, which at times have included entire companies or more being destroyed at a time. It is a point of pride for the Imperial Fists that the Chapter can not be fully defeated so long as one battle-brother remains on Phalanx to begin the process of reconstituting even the most grievous attrition. 
The Imperial Fists also maintain a Chapter Council composed of the Chapter's captains. The full purpose of the Council is not clear, but includes settling disputes between members of the Chapter and serving as a court in which the Chapter Master can hear the cases of the disputants and render his judgement, including punishment for offenses.
Disposition and Culture
The culture of the Imperial Fists articulates their genetically predisposed obsession with will power and pain into a coherent set of practices concerned with achieving uncompromising self-discipline and maintaining complete order.  The Chapter remains noted for its stern attitude and appears to outsiders as somber, cheerless warriors, though those who know them better, such as the Blood Angels recognize their inner passion. Imperial Fists customarily avoid wresting on the laurels of past accomplishments and instead find purpose in the performance of additional great deeds.
The Junker Model of Behaviour
The basic structure of Chapter culture is derived from the "Junker model of behaviour" belonging to the "ancient Prussic code" of Terra. The model demands dedication to meticulous detail in both military operations and individual conduct. In military operations, fastidious attention to detail is a hallmark of the Chapter's superlative planning and preparations. Similarly, every detail of an individual battle-brother's conduct is structured by the quest for flawless discipline and the obsession with punishment as penance for the smallest inadequacy, failure or infraction. [3b] In each case, the Chapter's genetically programmed obsession with will power and order are the guiding principles.
As part of their Junker tradition, the Imperial Fists practice Honour Duels, a ritual imparted to the Chapter by a handful of Terran battle-brothers. Honour Duels serve to settle disputes between members of the Chapter. The duel itself consists in two battle-brothers being stripped to the torso, dawning protective eye-wear and having their feet locked into blocks at a fixed range. A third battle brother acts as a judge, presiding over the duel wearing a black robe and helmet to conceal his identity. Salutes between the contestants and judge commence the duel and the two battle brothers engage each other with tungsten epees, ending at first blood drawn from the face. The ritual distributes honour to both battle brothers: the bested Marine accepts responsibility for the dispute and apologises, thereby honouring the victor, while the resulting scars of a loss are looked positively upon by other members of the Chapter, thereby conferring honour upon the loser. [3d] [3g] [6d]
The Imperial Fists are known to practice Scrimshaw using bones from the hands of their dead. After battle, Space Marines who distinguished themselves in the recent combat are awarded the skeletal hands of fallen battle-brothers,[3e] the individual bones of which are adorned with carvings, designs, and otherwise ornamented. Scrimshaw is undertaken solemnly by Marines of the Chapter and seen as an opportunity to practice mental discipline, focus, and attention to detail. Finished scrimshaws are worn as jewelry and ornamentation, particularly by officers.[3f]
Pain and Punishment
The Imperial Fists have developed particular cultural practices which tend to their obsession with conquering pain and penance. Chief among them is punishment that makes use of a device called the pain glove, which is both imposed by superior officers and self-inflicted. The pain glove encases the whole body and stimulates pain neurons, causing excruciating pain without inflicting any physical damage. The function of the pain glove goes beyond simple punishment in the sense of negative-reinforcement and includes positive spiritual value. Marines endure the extreme pain of the device by disciplining themselves to meditate on the glory of Rogal Dorn, thereby perfecting their spiritual communion with their Primarch.[6a]
So central is pain to the culture of the Imperial Fists that the Chapter seems to have developed a philosophy on the subject. As recited by anonymous Chaplain, "Pain is...a lesson that the universe teaches us. Pain is the preserver from injury. Pain perpetuates our lives. It is the healing, purifying scalpel of our souls. Pain is the wine of communion with heroes. It is the quicksilver panacea for weakness - the quintessence of a dedicated existence. Pain is the philosophic vitriol which transmutes mere moral into immortal. It is the Sublime, the golden astral fire!"[3c]
The Imperial Fists take their potential recruits from many worlds, among which are Terra, Necromunda, Pharos, and Inwit. On each of these worlds they maintain a Chapter keep. However they have no special rights as to where they recruit their neophytes. The Chapter also conducts ad-hoc recruitment as needed, which can involve intervening in ongoing conflicts to recruit the most talented warriors taking part in the fighting.  Once recruits are selected, their criminal record is examined, and they undergo a battery of tests: musculature, psychological profile ("Psychosis level"), psychic level, eye reflexes, intelligence, the ability to shoot, pain resistance, dexterity. Recruits spend six months in the fortress-monastery where they learn proper Imperial Gothic through a hypnocasque before undergoing their initiation in the "tunnel of terror." In the latter, they face extreme heat, cold, empty space, etc. The severity increases along the way. If the initiate passes, he becomes a cadet and the symbol of the Imperial Fists is marked on his buttock. Then begins the indoctrination, training and the actual surgery that transform them into Space Marines. To celebrate the introduction of the Preomnor implant, cadets eat poisonous plants, venomous animals, etc. For the Omophagea, they consume meat (some of the meat they eat is human flesh) and must divine from the meat a few details about the actual animal. After the initiation ceremony, the cadet's family is informed that their child has become a Space Marine.
In all, the Imperial Fists has created dozens of successor Chapters, more than any other Chapter other than the Ultramarines. Originally, the Imperial Fists Legion only sired two Second Founding chapters, although some versions of the Codex Astartes states that three or more were created. As the Legion was heavily depleted by the Horus Heresy, the legion could only be divided three or four times. However, Later foundings involved Imperial more Fists successors than early foundings because of the proliferation of viable gene-seed stocks.
Unlike other Legions, the gene-seed from the Imperial Fists stayed strong and pure, creating a basis for future foundings. Also unlike other Legions and their Successors, the Imperial Fists and their successors are quite different from each other. When it was split, the views of the individual Space Marines chosen as founders and leaders determined the chapter they succeeded into; the Imperial Fists retained those Marines most loyal to the Primarch; those that were unable to accept the constraints of the Codex became the Black Templars; and those who embraced the Codex became the Crimson Fists. Subsequent Foundings of Imperial Fists Successors were created according to one of those viewpoints, depending on how they were created, sometimes trough officers seconded from their Progenitor, until the Succesor Chapters developed their own experienced leadership.
It is noted that the Imperial Fists successor Chapters form a particularly tightly knit brotherhood of Space Marines, three of which are known to participate in the Feast of Blades, including the Imperial Fists. 
Noted Elements of the Imperial Fists
Relics and Artifacts
- Fist of Dorn
- Dorn's Arrow (in the possession of the Crimson Fists)
- Column of Glory
- Pillar of Bone
- Liber Honorus Imperial Fists
- Remains of Rogal Dorn
- Stormrod - Arcane Crozius of Tharhant
- Soulspear (in the possession of the Soul Drinkers)
- Liber Mithros
- Liber Proditor Armorum
- Liber Honorus Imperial Fists
- Sword of Sebastus
- Bones of Osrak
- Eye of Hypnoth
- Angel of Sacrifice
- Banner of Staganda
- Fortress-Monastery Phalanx
- Victory Class Battleship Tribune (destroyed)
- Battle Barge Hammer of Terra (destroyed)[12c]
- Battle Barge Storm of Wrath[16d]
- Battle Barge Spear of Vengeance[16d]
- Gothic Cruiser Imperial Power
- Strike Cruiser Titus
- Strike Cruiser Shield of Valour[16e] (captured by the Iron Warriors)
- Strike Cruiser Capulus[6b]
- Strike Cruiser Vengeance Incandescent
- Strike Cruiser Terrible Angel[15a]
- Strike Cruiser Justita Fides[27b]
- Strike Cruiser Triumphant
- Strike Cruiser Drostican's Deliverance
- Gladius Frigate Shield of Terra
- Gladius Frigate Will of Dorn
- Nova Frigate The Death of Lo Chang
- Starfort Endeavour of Will
- Starfort Bastion Inviolate(Lost)
- Sky Fortress (Destroyed)
- Wings of Dorn
- Primarch Rogal Dorn
- Captain Sigismund, 1st Company.
- Captain Halbrecht, company unknown.
- Captain Alexis Polux, 405th Company.
- Captain Efried, 3rd Company.
- Captain Camba-Diaz, company unknown.
- Captain Demetrius Katafalque, company unknown[32a]
- Captain Amandus Tyr, company unknown
- Archamus, Master of the Huscarl .
- Chapter Master Lazerian
- Chapter Master Vladimir Pugh
- Chapter Master Vorn Hagen, Current. (Former Captain, 5th Company.)
- Captain Darnath Lysander, 1st Company, current.
- Captain Tor Garadon, 3rd Company Commander
- Captain Taelos, 10th Company.
- Captain Lexandro D'Arquebus, company unknown, forwarded to the Inquisition.
- Captain Quirion Octavius, company unknown, forwarded to the Deathwatch.
- Reclusiarch Lycaon 
- Chaplain Lo Chang, 10th Company.
- Chaplain Carnak, 5th Company.
- Chaplain Markov (Now a Dreadnought)
- Chief Librarian Xeros Darsway
- Librarian Franz Grenzstein, company unknown.
- Sergeant Julan, temporary 1st Company commander
- Rhetoricus, company unknown.
- Nidon, 5th Company.
- 1: To Cleanse The Stars by Andy Chambers and Matt Keefe p. 23
- 2: Index Astartes II: Imperial Fists
- 3: Space Marine (Novel), Ian Watson
- 4: Harlequin (Novel) by Ian Watson, Chapter XX
- 5: The Art of Clint Langley[Needs Citation]
- 6: Sons of Dorn (Novel) by Chris Roberson
- 7: The Flight of the Eisenstein (Novel), James Swallow, Chapter XIV
- 8: Index Astartes IV: Crimson Fists
- 9: Imperial Armour Volume Two - Space Marines and Forces of the Inquisition
- 10: Horus Rising (Novel) by Dan Abnett, Part One, Chapter Six, pp. 130–133
- 11: Age of Darkness (Anthology) Christian Dunn, Black Library Product Description
- 12: Horus Heresy (Artbook Series): Collected Visions
- 13: Blood Games (Short Story) by Dan Abnett – Tales of Heresy (Anthology): p. 53
- 14: Mechanicum (Novel) by Graham McNeill
- 15: Codex: Black Templars (4th Edition)
- 16: Codex: Space Marines (5th Edition)
- 17: Codex: Space Marines (4th Edition)
- 18: Gauntlet Run (Short Story) by Chris Roberson
- 19: White Dwarf 286 (UK): The Eye of Terror, pp. 69–70
- 20: Phalanx (Novel) by Ben Counter: Chapter Two
- 21: Warhammer 40,000 5th Edition Rulebook, p. 142
- 22: Codex: Cityfight pp. 74–78.
- 23: Imperial Armour Volume Ten - The Badab War - Part Two, pp. 84
- 24: White Dwarf 305 (UK), pg. 104
- 25: Ultramarines - A Warhammer 40,000 Movie
- 26: Index Astartes: The Hands of the Emperor
- 27: Storm of Iron (Novel) by Graham McNeill
- 28: White Dwarf 302 (US), pp. 84–85
- 29: Index Astartes: Rhino APC
- 30: The Lightning Tower by Dan Abnett, pp.7–8
- 31: Codex: Chaos Space Marines (3rd Edition, 1st Codex), p. 32
- 32: Legion of the Damned (Novel) by Rob Sanders
- 33: Deathwatch: Rites of Battle, p. 66
- 34: Endeavour of Will (Novella) by Ben Counter
- 35: Codex: Necrons (5th Edition) p. 21
- 36: Black Library
- 37: Deathwatch: Rites of Battle, p. 51
- 38: Angel Exterminatus (Novel), by Graham McNeill, Chapter 7, pp. 119–123
- 39: The Crimson Fist (Novella) - Shadows of Treachery (Anthology), by John French
- 40: Codex: Space Marines (6th Edition), pp. 40–49
- 41: Sentinels of Terra, The 3rd Company's Triumph
- 41a: The Infestation on Drashin
- 42: Sentinels of Terra, The Crusade of Thunder
- 43: Malodrax (Novel) by Ben Counter Ch.1
- 44: Imperial Armour Volume Two p. 18
- 45: Seventh Retribution (Novel), K-Day, K-Hour, pp. 49–50
- 46: The Horus Heresy Book Three pg.56-77
- 47: Dataslate: Space Marines Strike Force Ultra (Background Book), pg. 13
- 48: Dataslate: Space Marines Strike Force Ultra (Background Book), pg. 10
- 49: Sentinels of Terra, The Sons of Dorn
- 50: Sentinels of Terra, The Storm Breaks
- 51: How to Paint Space Marines, pg. 78
|Loyalist||I - Dark Angels · V - White Scars
VI- Space Wolves · VII- Imperial Fists
IX- Blood Angels · X- Iron Hands
XIII- Ultramarines · XVIII- Salamanders
XIX- Raven Guard
|Traitor||III- Emperor's Children · IV- Iron Warriors|
VIII- Night Lords · XII- World Eaters
XIV- Death Guard · XV- Thousand Sons
XVI- Luna Wolves/Sons of Horus · XVII- Word Bearers
XX- Alpha Legion