IA: Knights of Madrigal

[Sigmarius]

The Knights of Madrigal have not always carried that cognomen. They began their life under a different name: Templars of Dorn. This is is their story.

 

 

Founding

 

The Templars of Dorn draw their name and gene-seed from the Praetorian of the Emperor, Rogal Dorn, Primarch of the VIIth Legiones Astartes. Though the chapter is old, it is relatively obscure given its age, often being overlooked in the vast turning wheels of Imperial bureaucracy. However, their anonymity does not mean the Templars have not gained battlefield honors and recognition.

 

The history of the Templars is rooted in Abaddon’s Second Black Crusade, and an assault squad sergeant named Octavianus. After leading his squad to glory on numerous occasions, he was promoted to lead the 5th Company of the Imperial Fists. Octavianus led the 5th for several decades before he was chosen for a greater honor. His most glorious achievement was the breaching of the Repulsive class heavy cruiser [REDACTED]. Leading elements of the 5th and 1st companies in the action, Octavianus’s men captured and scuttled the ship. Octavianus is said to have slain five Traitor champions in single hand to hand combat.

 

When it was decreed that a Third Founding would commence, Octavianus’ achievements and success as the Captain of the 5th led to his being called upon to be the Chapter Master of one of the new chapters. In honor of the primarch, as well as recognition of one of the great heroes of the Imperial Fists, Octavianus chose the name Templars of Dorn. Their name, combined with their livery, would leave no doubt as to where the Templars trace their roots.

 

Following the third founding, the chapter brothers served alongside fellow chapters on missions in the glory of the God Emperor. As their ranks of battle brothers swelled, they began to stand on their own and were given their first true mission: join the Tecridian Crusade, and scour the sub-sector of traitors. They were accompanied in the crusade by elements of the Imperial Fists and numerous Imperial Guard regiments.

 

 

The Tecridian Crusade

 

The Tecridian Crusade was a brutal campaign that in truth was more of a continuation of The Scouring than an independent crusade. System by system, planet by planet, crusade forces pushed back the forces of the traitor legions and their cultists, reclaiming multiple Imperial worlds. While the vast majority of these forces were renegade elements of the Imperial Army and civilian cultists, they were led by the greatest foes of the VIIth Legion, the whore-sons of Perturabo, the Iron Warriors.

 

After years of conflict, the enemy was pushed from every planet aside from the heavily populated and well defended Tecrid Prime, the prior seat of Imperial Authority before the occupation of the forces of Chaos. The Imperial forces debated heavily on the best course of action, but eventually the decision was reached to have Octavianus lead the invasion. The Chapter Master consolidated his forces into full battle companies, with his marines being supported by the forces of the Imperial Navy and the remaining Guardsmen for the assault of four major cities on Tecrid Prime. They would identify and eliminate the command and control nodes in each city. The 10th Company, a scouting company devastated through the course of the campaign to less than one quarter their original strength, would remain behind.

 

The assault on Tecrid Prime was by all accounts a barely mitigated disaster. The 3rd Company was destroyed when their primary landing site, a vast platform for bulk lifters, was annihilated by a massive series of melta charges. The 4th Company never made landfall. Hidden anti-air emplacements, along with especially tenacious Chaos air to air fighters, wiped the entire company out of the sky. The 2nd Company was systematically surrounded and slaughtered by the combined might of the Iron Warriors. It was during this battle the unthinkable happened: a dreadnought, known as Venerable Brother Nero, was captured by the traitors.

 

Only the 1st company seemed to have any measure of success in defeating their enemies. Slowly, block by block and street by street, the Templars made their way towards the fortress where the leader of the traitor forces waited. During the assault on the fortress, Octavianus learned of the capture of Nero from the 2nd and realized that with the losses incurred his chapter was down to barely one hundred Astartes. It is said in hushed whispers that he channeled the cold fury of his gene-father, and became the incarnation of wrath. After several hours of fighting, his fury unleashed, Octavianus forced his way into the command center. There, he battled the traitor commander in single combat while the surviving members of the 1st Company's squads continued the eradication of the remaining forces of Chaos.

 

The battle between Octavianus and the traitor commander lasted for hours, all the while their respective troops warred against each other. In the end only a few members of the 1st company remained to see the end of the personal battle between Octavianus and the traitor commander. Taking advantage of a gap in Octavianus’s defenses, the traitor commander plunged his two power swords into the Templar’s chest. Determined to deny the enemy the victory he thought he had achieved, Octavianus bellowed in rage and drove his gladius up through the bottom of the traitor’s head, bisecting his brain.

 

Octavianus was rushed back to the chapter flagship, where he is believed by the members of the Chapter to have succumbed to his wounds.

 

 

The Templars Rebuild

 

Following the conquest of Tecrid, the Templars returned to their ships to take stock of the grim news. Of the four companies that had made planetfall, less than one hundred battle brothers remained, most of them the unascended members of the 10th Company. While the wider Imperium was told of a great victory, behind closed doors, whispers of Octavianus’s folly mingled with those of reintegrating the Templars back into the Imperial Fists. Into these troubled times stepped the sole surviving member of Octavianus’s bodyguards, the man who would take up the mantle of the Chapter Master: Lucius Domitian Aurelianus. Known to his brothers as Aurelian, and to the wider Imperium as The Domitian, he led his chapter back from the brink of extinction.

 

Through a combination of political maneuvering, powerful friends within the Imperial Fists, and sheer stubbornness, Aurelian prevented the High Lords of Terra from reintegrating the Templars back into the Fists. While a sizable contingent of Imperial Guard forces kept the peace on Tecrid, the Templars went into seclusion to rebuild. Slowly, over the course of two centuries, the Templars rebuilt their strength. Using the population of the Tecrid system as their primary recruiting source, especially the wild nomad warriors of Madrigal, the Templars were able to refill their ranks, and return to full strength.

 

During this time Aurelianus led the system to an age of prosperity, though Tecrid’s sister planet of Madrigal was left mostly untouched. It was during this time that Aurelians was able to begin indulging his love for knowledge and reading. In time, the chapter built a vast Librarium in the mountains of Madrigal, and it took its name Bucherei, from a local Madrigalan word. This endeavor was assisted by the larger than normal number of Librarians in the chapter. In time, the day to day running of the Librarium was taken over by a group of women from across Madrigal, viewing service there as their calling from the Emperor and his Angels.

 

 

The Shaming of the Templars

 

In M35, the Imperium experienced a treason greater than any seen since the Horus Heresy. In the galactic west, within Segmentum Pacificus, the Ur-Council of Terra rejected the authority of the High Lords of Terra and established what historians would later dub the Nova Terra Interregnum.

 

Throughout the centuries of the rebellion, the Templars of Dorn undertook multiple crusades and actions throughout the Segmentum in an attempt to bring the traitorous “Imperium” back into the fold. In 974M35 as the Templars were nearing the end of their most recent crusade, an astropathic message begging for aid was received from the one place the Templars never expected: Tecrid.

 

When news of the rebellion reached the Templars, their new chapter master, Berengar, was apoplectic. After everything he and his brothers had done for the populace, Berengar would not allow this treason to go unpunished. That punishment would be severe, and it would be used as an example for other worlds that presumed to rebel against Imperial authority. Every hive city on Tecrid, and nearly every other city throughout the system had rebelled. Only the great library, defended by a small contingent of Templars and hastily trained Librarium Sisters had managed to hold off the treasonous masses.

 

Berengar mustered the full remaining might of his chapter, and set them to a singular task: hunt down and exterminate all traitors, their supporters, and those deemed not to have fought hard enough against them. He unleashed his men across the system, ordering they regain compliance from the populace, and to show no mercy in their actions.

 

What followed has become known as the Days of Shame. An entire chapter of Astartes channeled and unleashed their rage against the populace of a system in revolt. Men, women, even children were killed by the millions, the slaughter being so extensive that the Templars repeatedly ran out of ammunition, forced to unleash their wrath with their blades. For the citizens of the homeworld, it seemed as if Hell itself had been unleashed upon them. All seemed lost, until salvation arrived, in the form of fire-breathing dragons.

 

 

Intervention

 

Responding to one of the first astropathic messages sent by the Planetary Defense Forces when the rebellion began, an Astartes strike cruiser entered the Tecrid system and took up orbit over the homeworld. A small force of Salamanders had arrived and requested an audience with Berengar. Included in the Salamanders force that made planetfall was a revered brother in Dreadnought armor, an ancient by the name Ko’van.

 

What the Salamanders saw when they landed appalled them, the indiscriminate slaughter by loyal sons of the Emperor shaking them to their core. Entire habblocks leveled by artillery with no regard for the civilian populace. The Salamanders did what they could to mitigate the bloodbath, but were largely ineffective. They made their way to the front line where Berengar was leading his men to ruin.

 

Ko’van confronted Berengar and demanded the atrocity be stopped immediately. Berengar, his blood burning through his veins, turned on Ko’van and told him to leave the field if he was too cowardly to conduct the Emperor’s work. As they argued, Ko’Van seized the Chapter Master’s thunder hammer mid-swing, preventing Berengar from slaying an unarmed civilian.

 

Enraged at the interference, Berengar struck Ko’van’s armored sarcophagus. Ko’van took hold of Berengar in his Dreadnought fist and, turning his vox speakers to their loudest, demanded Berengar cease in the name of the Emperor and His praetorian. Berengar, realizing his life was quite literally in the hands of an enraged war machine, paused. Ko’Van demanded that the Templars cease their culling, telling him that Dorn would be ashamed of the Templars' actions. Berengar, his soul shaken by the words of the venerable warrior, agreed, and ordered his men back to the fleet. Ko’van returned with them, leaving the remaining Salamanders to regain control of Tecrid.

 

Ko’van and Berengar traveled to the great library on Madrigal where they secluded themselves from the rest of the Templars. There, in the presence of millenia of knowledge, they debated philosophy, duty, and strategy. It was during this time that Ko’Van told Berengar of one of his greatest days, the day he heard Rogal Dorn and Vulkan debate the role of the Astartes in the Imperium. Dorn stated that it was their duty to serve the Emperor above all else, no matter the cost, while Vulkan argued that service to the Emperor also meant serving the people, for without the people there is no Imperium.

 

It was during this period of debate and soul searching that Berengar made the decision to allow Ko’Van to be told of one of the chapter’s most ancient secrets, one known only to him, the Chief Epistolary, the Master of Sanctity, and the Master of the Forge. Deep in the hidden vaults of Bucherei lay a secret chamber. Hewn from the raw stone of the surrounding mountain and fitted with the necessary mechanisms, the chamber held a dreadnought of ancient origin. Housed within the sarcophagus, kept in stasis for centuries on end, lay the living remains of the Templars’ first chapter master, Octavianus.

 

Ko’van encouraged Berengar to go and speak with the ancient master, tell him of what the last few millenia had done to the soul of the chapter. Berengar agreed, and for the first time in 500 years, Octavianus was awoken from his slumber. No one save Berengar and Octavianus knows what was said during that meeting, but after days of conversation and even longer in quiet contemplation, Berengar came to a decision. He summoned the Chaplains and gave his decree: the Templars would go on a penitent crusade and re-discover their own humanity. There was resistance at first, but soon all the chaplains acquiesced to Berengar’s wishes.

 

Leaving the system in the hands of Imperial Guard reinforcements, under the command of the Salamanders, the Templars began their crusade. For half a century, the Templars of Dorn traveled the Segmentum, answering any call for aid they received, and oftentimes lingering for several weeks after the battle to lend initial assistance to rebuilding efforts.

 

After the crusade, the Templars returned home to a peaceful system. With their return, they brought back something extremely unusual for a chapter of Astartes: faith in the divinity of the Emperor. Though their beliefs differed, oaths of brotherhood were sworn between the Templars and the Salamanders, and to the present day the friendship between them remains close.

 

 

The Order of the Pierian Spring

 

In the aftermath of the Age of Apostasy and the Plague of Unbelief, the Ecclesiarchy came to the Tecrid system in force. They brought confessors and preachers with them to ensure that the Imperial Cult was well established in the system. They also brought an Order of Establishment, a writ declaring that the women that ran the librarian a sort of monastic tradition would be officially formed into a convent of the Ordo Dialogus of the Adepta Sororitas to further protect the sanctity and knowledge stored within from the corruption of Chaos. Though there was initially resistance to the plan on the part of the Templars, the arrival of an Ordo Hereticus Inquisitor a short time later convinced the Templars current chapter Master, Godric, that he did not want to deal with the inevitable headache that would arise from resisting the Ecclesiarchy. The order was founded, but the records of its original name have been lost to time.

 

In time the order’s name changed to the Order of the Pierian Spring, although the origin of the name is a mystery to the Astartes. What is known is that around the same time as the Sisters changed their name, the Templars made another drastic change to their identity. The chapter master at the time, a legendary warrior named Alaric, had spent several days sequestered in the deep vaults. Most of the Templars believed him to be in quiet meditation, however he was actually in deep conversation with Octavianus.

 

Octavianus told Alaric of a vision he had seen, of a conversation between Dorn and the Emperor on the ramparts of Bucherei. Octavianus told Alaric that during the vision the Emperor had referred to the Templars as his “knights of Madrigal”, and Octavianus believed the chapter should change their name to better fit their mindset. Alaric resisted at first, however after days of debate with Octavianus, and later the top leadership of the chapter, Octavianus made the decree. From that day forward, the Templars of Dorn would be no more. They would be forever known as the Knights of Madrigal. To accompany their new cognomen, they would also change their armor colors and badge. The proud yellow of the Imperial Fists would be retired and replaced with a pure silver with blue shoulders. The mailed fist chapter symbol would be replaced with a sword and sunburst, to represent their dedication to martial prowess and enlightenment.

 

 

Cicatrix Maledictum and Imperium Nihilus

 

The fall of Cadia and the opening of the Great Rift had a devastating effect on the Knights. Most of the chapter was scattered around the galaxy, assisting in various conflicts, mostly on the far side of the rift in what is now called the Imperium Nihilus. The current Chapter Master, Marcus Vipsanius was within the Segmentum Solar with a contingent of the 1st Company when the Great Rift opened when the news came: Roboute Guilliman had returned.

 

Marcus and the 1st Company traveled to the Sol system at this news, and in time, Marcus was granted an audience with the Primarch. Believing most of the Knights to be lost, Guilliman informed Marcus that they would be reinforced with the new Primaris Marines. Marcus accepted this great honor, and began the process of readying his existing troops for their imminent reinforcements. Once their new Primaris brethren were integrated into their existing forces, the Knights joined the Indomitus Crusade, with every conflict leading them towards their home.

 

 

Homeworld

 

The Tecrid system is the home of the Knights’ homeworld and Fortress-Monastery, Bucherei. In what is seen as a rather unique celestial orientation, Tecrid shares a stable orbit with it’s sister planet, Madrigal, upon which the Bucherei is located.

 

Madrigal is a primarily agrarian and barely settled world, home to tribes of nomads and small settlements, including numerous monastery outposts of the Order of the Pierian Spring. It is by the decree of the Knights that Madrigal will never be heavily settled or fortified, in order to maintain their spiritual connection to the roots of the people.

 

Unlike it’s agrarian counterpart, Tecrid Prime is the home of several hive cities, and holds the seat of the Administratum in the system. It is also the primary trading hub planet, and contains the system’s primary astropathic choir.

 

The third planet in the system, Vicorius, is outside the stellar habitable zone, however extensive terraforming eons ago allowed settlers, for a time. By the time of the Great Crusade the inhabitants of the third planet had been forced to live mostly in their few major cities protected by ancient environmental shielding.

 

The first and innermost planet in the system is known as Acherus. The name is fitting given the world’s extreme tectonic activity and heat, caused by its proximity to the system’s star.

 

The Tecrid system is surrounded by an extensive and dense asteroid belt, making navigation in and out of the system difficult. However, the belt’s natural shielding of the system as well as it’s proximity to the systems Mandeville Point have made it an excellent defensive addition and training locale, and the Chapter has utterly refused to entertain the idea of thinning or removing this natural defense.

 

 

Gene-Seed and Beliefs

 

The Knights draw their gene-seed from the Primarch of the VIIth Legiones Astartes, Rogal Dorn. As such, they too experience some of the same degradation of abilities as their Imperial Fist brethren, specifically a non-functioning Betcher’s Gland and catalepsian node. However, the more pure gene-seed stock contained within the new Primaris Marines seems to have alleviated the issues in the new breed of Astartes. They also inherited their gene sire’s legendary stubbornness, though it appears to be slightly less extreme than their Imperial Fists cousins.

 

The Knights believe that glory for the individual should be recognized only in the most extreme of circumstances, and this belief extends to the glory of the chapter as well. The origins of this belief extend back to the Horus Heresy. It was Octavianus’s firm belief that a major influence on the Arch-Traitor Horus and his thrice-damned brothers was that they bought into their stories of glory, and began to believe they were better than they actually were. Therefore, personal and chapter glory would be limited. This has led to a more subdued approach in the ornamentation of the armor and banners of the chapter. Outside of company and chapter champions, banners are almost completely absent from the Knight’s battlefield appearances. It is for this reason why so few of the past chapter masters are revered in a similar manner to the Knights’ other Astartes cousins.

 

The Knights firmly believe that it is their duty to be good stewards of humanity, and where reasonably possible, civilian casualties should be minimized. This belief has led some outside the chapter to erroneously believe that the Knights will sacrifice the mission to protect innocents, and that they will not declare Exterminatus. These ideas are inherently false and only continue as the Chapter has not yet faced a situation that required the ordering of Exterminatus rather than approach via conventional means. So far, their beliefs have held true.

 

A curious aspect of the culture of the Knights is their heavy focus on retaining and teaching their chapter's history. Octavianus was known to be an ardent student of history, and as such, the librarius of the Knights is considerably more developed than those of their fellow Astartes chapters. Whether the extensive librarius led to the chapter seeking more librarian battle psykers, or if having more librarians has led to a more extensive Librarius is unknown, but most in the chapter believe these factors perpetuate each other. In addition, the Knights are unique in the duties of the Chaplain corps. While the Librarians maintain the history of the Chapter, it is the Chaplains who are tasked with teaching that history and ensuring the legacy of the Knights of Madrigal endures the tests of time and constant risk of the taint of corruption.

 

 

Organization

 

While there have been some necessary organizational changes in the opening of the Cicatrix Maledictum and the subsequent introduction of Primaris Marines, the core principles of the Knights’s organizational doctrines have remained unchanged. In some respects, the Knights do follow the Codex Astartes as laid out by the Primarch Guilliman. However, in many aspects the chapter deviates from that venerable tome.

 

At the core of the Knight’s structure is the battle company. Unlike their more Codex compliant cousins, the Knights do not divide their companies into dedicated roles. Rather each company is, for the most part, entirely self-contained. Other than chapter level assets such as the Librarium and Chaplaincy, each company is organized and equipped to be fully self-contained and as self-sufficient as possible. Each company has its own veterans, assault squads, bikes, terminators, and scout squads. These units are usually not seconded from other companies unless there is an unfulfilled need within a company.

 

Before the introduction of Primaris Marines, the average size of the Knights battle company was approximately one-hundred twenty-five battle brothers. This number does not account for the brothers responsible for manning the chapter’s tanks and aircraft, as well as other specialists such as apothecaries, librarians, techmarines, and chaplains.

 

Currently, the chapter organization is composed almost exclusively of Primaris Marines. While the Knights still hold out hope that they will find their lost brethren, the realities of war have dictated that the chapter adapt. With the exception of the Master of Sanctity and his personal retinue of terminator clad brethren, the entirety of the Knights chapter command have crossed the Rubicon Primaris.

 

The official organizational structure of a company of the Knights of Madrigal is as follows:

 

Company Captain

Company Epistolary

Company Chaplain

Company Apothecary

Company Techmarine

Company Ancient

Company Command Squad

2x Primaris Lieutenants

 

Squad #

1. Veteran Heavy Intercessors (10) w/ transport

2. Heavy Intercessors (10) w/ transport

3. Heavy Intercessors (10) w/ transport

4. Intercessors (10) w/ transport

5. Intercessors (10) w/ transport

6. Veteran Assault Intercessors (10) w/ transport

7. Assault Intercessors (10) w/ transport

8. Hellblasters (10) w/ transport

9. Eradicator Squad (5) w/ transport

10. Eradicator Squad (5) w/ transport

11. Bolter Aggressors (6) w/ transport

12. Flamer Aggressors (6) w/ transport

13. Bolter Inceptors (6)

14. Plasma Inceptors (6)

 

Phobos Lt.

Phobos Librarian

Phobos Apothecary

Squad #

1. Infiltrators (10)

2. Incursors (10)

3. Reivers (10)

4. Suppressors (3)

5. Suppressors (3)

6. Eliminators (3)

7. Eliminators (3)

 

Support Elements:

2x Outrider Squads (3)

Invader ATV Squad (3)

2x Redemptor Dreadnought

Storm Speeder Hailstrike

Storm Speeder Thunderstrik

Storm Speeder Hammerstrike

2x Firestrike Servo-Turrets

2x Hammerfall Bunkers

2x Gladiator Lancers

2x Gladiator Reapers

2x Gladiator Valiants

 

It should be noted that these numbers are considered ideal by the chapter’s planning masters, and due to combat losses, especially after the opening of the Cicatrix Maledictum, these numbers do not necessarily reflect the current fighting strength of the Knights.

 

 

Combat Doctrine

 

The Knights prefer the use of heavy weapons in their defensive positions, and the use of deep striking units to drop down behind enemy lines in order to eliminate enemy commanders and heroes. In addition, a heavy emphasis is placed on trying to gain and maintain battlefield air superiority, however at the moment this is difficult as nearly all of the chapter’s air assets have been lost.

 

Due to the abnormally large size of the Knights’ librarium, battle psykers are a near constant presence on the field, and are frequently placed in command of chapter deployments. Oftentimes these psykers will join assault squads in order to bring the Emperor’s wrath directly to enemy commanders in an effort to ensure quick, decisive victory and prevent the prolonged attritional combat that often follows combat against the traitor legions.

 

 

Heroes of the Chapter

 

Octavianus: Formerly an assault sergeant of the Imperial Fists and the first chapter master of the Templars of Dorn, Octavianus is considered by some in the chapter to be its greatest hero. Stories tell of countless Chaos champions slain and numerous critically timed assaults breaking enemy lines at crucial moments.

 

Perhaps Octavianus’s greatest combat achievement was the slaying of the enemy warlord during the Tecrididan Crusade. Though Octavianus was believed by most of the chapter to have been slain during the battle with the Chaos warlord, in fact he was placed into one of the chapter’s Contemptor Dreadnought bodies. However, by his own order, his identity has been kept secret from the chapter, known only to 4 members of the chapter at any time: the Chapter Master, the Chief Epistolary, the Master of Sanctity, and the Master of the Forge. The reason for Octavianus’s order is known only to him.

 

Berengar: Credit with the re-birth of the Templars, Berengar reforged the soul of the Templars from one of wrath and anger to one of service and humility. He is also credited with forming the close bonds of friendship with the Salamanders that exists to this day.

 

Valerius Seramus: The current Chief Epistolary of the chapter, Valerius’s psychic might is legendary amongst his brothers. A gifted precognitive battle-psyker, Valerius uses his abilities to become a consummate one-on-one fighter. It is told that Valerius has slain warlords of every major enemy of the Imperium.

Edited August 31, 2021 by Brother Tyler
Font color and background changed to default, BBCode cleaned up.

[Minigiant]

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[Bjorn Firewalker]

This is well-written, overall. Erasing Dorn's name from the Chapter's, and removing the Imperial Fists' clenched fist from the Chapter symbol; can be viewed as an insult to the Primarch and the progenitor Chapter; how have the Knights convinced the Fists and other Fists successors this wasn't the case?

[Sigmarius]

Please edit the font colour to default and not white. Mobile users cannot view it

Sorry, I always do this stuff on desktop and always forget it messes up on mobile.

This is well-written, overall. Erasing Dorn's name from the Chapter's, and removing the Imperial Fists' clenched fist from the Chapter symbol; can be viewed as an insult to the Primarch and the progenitor Chapter; how have the Knights convinced the Fists and other Fists successors this wasn't the case?

That's a good point that I honestly had never thought about. I'll have to ponder that.

[Bjorn Firewalker]

A close relationship with the Black Templars can help alleviate suspicion the name and Chapter symbol changes were deliberate insults to their Primarch.

 

Have the then Knights of Madrigal Chapter Master tell the then Black Templars High Marshal the change was because the Knights had shamed their progenitor Chapter by committing the massacre, making them unworthy to bear the Primarch's name; that they go on a penitent crusade to regain their honor and the right to use the name "Templars of Dorn". Make sure the Black Templars will spread the news to other Imperial Fists successors, e.g., during a Feast of Blades. That should work.

Edited September 4, 2021 by Bjorn Firewalker

[Sigmarius]

A close relationship with the Black Templars can help alleviate suspicion the name and Chapter symbol changes were deliberate insults to their Primarch.

 

Have the then Knights of Madrigal Chapter Master tell the then Black Templars High Marshal the change was because the Knights had shamed their progenitor Chapter by committing the massacre, making them unworthy to bear the Primarch's name; that they go on a penitent crusade to regain their honor and the right to use the name "Templars of Dorn". Make sure the Black Templars will spread the news to other Imperial Fists successors, e.g., during a Feast of Blades. That should work.

I like this a lot. Thanks!