Knowledge speaks , Wisdom listens.
Background
Silent Legion are a successor chapter to the Blood Angels. They try to follow their founding chapters traditions as closely as they can as they believe it holds the key to overcoming the curse of the red thirst and black rage. After suffering a consistent attack on their homeworld from Ork forces and Eldar incursions, Silent Legion had fallen back to a few fortified positions, relying on shock tactics after straining enemy positions to deter enemy advancement. Which they would do by utilising any means at their disposal.
Unable to get a constant stream of new recruits to combat the onslaught, their numbers had dwindled over the centuries but the chapter held what ground they had left in the name of the Emperor. This was done by targeting key points in the enemy supply lines to cripple them just enough to overcome odds. As a result of using this approach the Legion has become rather sufficient at reconnaissance (including with use of psykers if required) and use it to find weak points in both offensive and defensive operations. This used along with their aggressive approach to breach the strain in an enemy line made for fast results from seemingly long drawn situations. However, the lack of manpower and resources meant that more often than not, land would soon fall once again from their control. Thus they had to choose very carefully what territories to hold, and what territories to attack and cripple.
It was not until a relief force from their founding chapter was sent to help secure their home world that Silent Legion was able to begin rebuilding. This not only strengthened their views but started a wind of change in the chapters less talked about beliefs, namely that they thought the successor chapters should unite under Dante and the banner of the Blood Angels. It was felt that this was the best approach to fortifying the Emperor's will and to preserve it in his image until his return.
All the same, they knew this was far from their ability in their current state so focused on rebuilding while aiding their founding chapter in the systems conflict. To do this they started to quickly set up a system wide intelligence link and relayed through whatever information they could gather, particularly beneficial to aggressive tacticians. This way they could be of most use despite their low numbers.
After the events on their homeworld and the developing scenario in their home system, the Legions intelligence links started to make a slight shift, specifically informing the Blood Angels and all other successor chapters nearby with key pieces of intel, that would more often than not result in chapters finding themselves fighting at one another's side. This was the beginnings of their efforts in their ever secret agenda but they were aware of the bite of the inquisitor and the politician and knew that this could in time be seen as something akin to the lodges of old. To counter this, they were sure to keep it to a strict intelligence only approach, though carefully planned to bring the chapters closer together.
The date of the chapter's founding is thought by some to be as far back as the third and sometimes even second founding, being formed from gene seed samples from multiple successor chapters. However the history of chapter is vastly unknown and more likely to have been as recent as M37 or M38. The chapter has lost some of its chapters history logs during the Waggh hitting their recruiting world and since regaining control they have been piecing together small pieces.
The world was feudal and temperate. Large warring states waged periodical assaults on one another in bids for power. The planet, large in size, ever prevented any state from gaining too much control by a large margin as in times of war, Borders were oft tested on all sides in name of vengeance, glory, honour or power. Then in times of peace the villages, towns and even capitals were haunted by the large hunting mammals that dominate the wilds.
Chapter fortifications net the worlds surface in a wide spread defensive grid. Each surrounded by thick forestry and jungle, hundreds of miles deep. Nurtured into existence by the chapters surfs to create hostile environments to mimic those one may find on a death world. This measure is used not only to train recruits and hone skills but to keep the populace at lengths from chapter ongoings. With wildlife that could tear apart a fully armoured astartes that was not on guard, it was more than suited for this task.
Where as most conflicts are waged off world, there have been constant interest shown by Eldar forces in form of raiding parties, ever increasing in number and frequency. The reasons for which remain unknown but potentially connected to the Slanesh presence that would emerge in years to come. The Eldar were every stealthy in their attacks on world. Hard to find and when found usually laying in ambush. Playing on brash aggression demonstrated by the chapter and punishing any mistake made relentlessly.
Early on in the chapters residence here, this forged some restraint in their approach to warfare. An early focus in detailed reconnaissance to help deal with the Eldar menace and prevent so many casualties from Ranger groups that seemingly always watched.
In growing Eldar activity system wide (particularly planetside), the Chapter developed the fortress net that is being repaired today. Expanding on the much weaker but suitable outpost spacing between a few major positions.
As the massive undergoing neared 65% to 75% completion, agressions escalated with Eldar forces. Believed to be in a desperate bid to prevent control of the world being lost and their outposts being discovered. It was never discovered if this was in fact the case as the events to follow prevented this.
The Elder engaged and gave up stiff opposition leading the field commanders to believe they were nearing an Eldar installation. Slowly being pushed back before breaking the Eldar routed, the Legion giving vicious chase determined to get a finish to the conflict only for the Eldar to vanish. Leading the Legion directly into chaos forces mostly made of cultist, they had taken hold in the more remote areas in this region and had been in the process of mass rituals in the name of Slanesh. Perhaps this was also known to Eldar forces.
Seemingly overnight, chaos power blots started to make themselves known planet wide and only increasing over the coming weeks. On that day however, the Eldar threat grew quiet for a time and a new war waged with the forces of chaos. The Feudal population easy prey for the corruptions.
It was months before the Eldar was seen again. What followed for the next seven years was the repression of the chaos incursion and the cleansing of corrupted populace. An act that most displeased the chapter and would, much like the Eldar, would become a recurring thorn in the Chapters side. In times to come the populace themselves would aid the Chapter in rooting out corruption but it would take a reckoning of cataclysmic proportions to bring such resourcefulness to pass. Combined with a lack of resources, off world operations and an era of darkness.
Twelve years from the day the corrupted wars began, work started on the lost fortifications to try and finally cement full control over the world, in turn making it easier to throttle what was left of wide spread corruption.
During these years, off world operations were cut back some to secure what was once a recruiting world, and fast becoming a home world. Activity in the system centred around the Planet that had acted as anchor for fleet operations and spurred the early development of the orbital station / fortress.
The Chapters relationship with the citizenry of the world had evolved over the years and now stood divided into three segments:
The Citizens
From whence new Astartes were brought into service. a crop familiar with warefare and taught its principles as though it were spiritual in nature. Recruits that would train in trials in the deadly jungles surrounding the planet fortifications. Trials in hunting, reconnaissance, sleep deprivation conditioning, endurance and physical prowess. Somewhat altered from traditions in Chapter history after the increasing Eldar attacks over the decades.
The Nobility
Not much contact was had with this portion of the population. What was, was generally conducted through chapter surfs as / or emissaries. This would only take place is the Chapter wished a change in society, a power to fall, a tradition to be created or altered. This order was rarely given directly from the Chapter to avoid presumptions by the nobility as to wants or desires. Rather, by issuing small tasks, or changes to multiple states that would result in the desired effects. This not only helped orchestrate the mindset of the nobility, but could had been used to coax out Chaos corruption.
The Planetary Militia
Recruited from those who had failed astartes trials or from those few too old, or even from the few who have made it through a death forest without prompt. The latter of which started the idea. Imperial reinforcements were thin, as were Legionaries and there were many fortifications to man. Part of this militia would, in years to pass, come to venture off world with the Chapter as an unofficial auxiliary. However it would take more than a jungle trial for this bond to gain strength.
After the founding of the codex, the chapter was formed. Saddened by the rift created between them and their fellow brothers and still reeling from the death of their primarch the chapter embarked upon an unofficial crusade of their own design. Setting off in guise of locating suitable recruitment worlds the chapter began striking out at enemy activity, pushing more often than not towards chaos activity. With the lack of recruiting world the chapter fast began to uphold the founding chapters virtue of tactics above most others in order to minimise losses. At times taking small numbers of recruits deemed worthy from worlds they passed.