Half-Eldar
Eldars have long drawn the covetous gazes of other races. Their generous lifespans, psyker affinity, and inherent grace each contribute to the admiration or bitter envy of their neighbors. Of all their traits, however, none so entrance their human associates as their beauty. Since the first two races came into contact with each other, humans have held up eldars as models of physical perfection, seeing in these fair folk idealized versions of themselves. For their part, many eldars find humans attractive despite their comparatively barbaric ways, and are drawn to the passion and impetuosity with which members of the younger race play out their brief lives.
Sometimes this mutual infatuation leads to romantic relationships. Though usually short-lived, even by human standards, such trysts may lead to the birth of half-elders, a race descended from two cultures yet an inheritor of neither. Half-eldars can breed with one another, but even these "pure blood" half-elders tend to be viewed as bastards by humans and eldars alike. Caught between destiny and derision, half-eldars often view themselves as the middle children of the world.
Background
Humans and eldars can produce offspring, and the product of such a union is a half-eldar. eldars are not prolific, and they do not look favorably upon those who couple with other races. As such, half-eldars are rare. History reveals certain prejudices against half-eldars. Humans are jealous of half-eldars' extended life spans. Eldars see them as proof of their race's weakening blood. In recent years, this bias has waned - wars and strife show how petty such prejudices are. In large cities, which consider themselves enlightened, half-eldars find little of the historic discrimination. Still, many individuals, particularly eldars, remain scornful of half-eldars and may or may not attempt to hide their feelings. Tensions with the Humans and other forces strain relationships among both races, and some allow this stress to manifest itself in anger against anything different from themselves.
They push themselves to excel in whatever their chosen field, whether to hope that success will help them fit in or to spite those who consider them inferior. One will not find a more dedicated priest, a more loyal fighter, or a more studious sicker than a half-Eldar. That's a half-Eldar will ever serve in high position in the Imperium is virtually impossible, but their desire for acceptance nonetheless drives many to volunteer whenever the Imperium has a need. They always face the chance that great heroism may give them the acceptance they have wanted all their lives.
Half-eldars are members of the imperium. Half-eldars socialize with humans more than with eldars, as the former are generally more accepting — and easier to find. In their wanderings and search for self, some half-eldars join the imperium or become independent. They sometimes find a home within the towns of the Xeno races, although the culture is so different from older or human culture that it seldom offers a comfortable fit for long. Their eldar heritage grants half-eldars a natural talent with psyker-related skills. However, a half-eldar does not enjoy a full eldar legacy that would otherwise bestow strong psyker abilities and control; however, a half-Eldar's blood does carry enough psyker heritage to offer some resistance to warp. They have a limited psyker ability lower than Trueblood Eldar, but greater than average human psyker, drawing upon their eldar heritage.
Physical Description: Half-elders stand taller than humans, but shorter than eldars. They inherit the lean build and comely features of their eldar lineage, but their skin color is normally dictated by their human side. While half-eldars retain the pointed ears of eldars, theirs are more rounded and less pronounced. Their eyes tend to be human-like in shape, but feature an exotic range of colors from amber or violet to emerald green and deep blue.
Society: Their lack of a unified homeworld and culture forces half-Eldars to remain versatile, able to conform to nearly any environment. While often considered attractive to both races for the same reasons as their parents, half-Eldars rarely fit in with either humans or Eldars, as both races see too much evidence of the other in them. This lack of acceptance weighs heavily on many half-Eldars, yet others are bolstered by their unique status, seeing in their lack of a formalized culture the ultimate freedom. As a result, half-Eldars are incredibly adaptable, capable of adjusting their mind-sets and talents to whatever societies they find themselves in. Even half-Eldars welcomed by one side of their heritage often find themselves caught between cultures, as they are encouraged, cajoled, or even forced into taking on diplomatic responsibilities between human and Eldar kind. Many half-Eldar rise to the occasion of such service, seeing it as a chance to prove their worth to both races. Others, however, come to resent the pressures and presumptions foisted upon them by both races and turn any opportunity to broker power, make peace, or advance trade between humans and Eldars into an exercise in personal profit.
Relations: Half-Eldars understand loneliness, and know that character is often less a product of race than of life experience. As such, they are often open to friendships and alliances with parent races, and less likely than most to rely on first impressions when forming opinions of new acquaintances. Those humans who admire Eldarkind see the parent as a living link or bridge between the two races. But this attitude often foists unfair expectations and elevated standards upon half-Eldars, and quickly turns to derision when they do not live up to the grand destinies that others set for them. Additionally, those half-eldars raised by or in the company of eldars often have the human half of their parentage dubbed a mere obstacle, something to be overcome with proper immersion and schooling in the eldar ways, and even the most well-meaning eldar mentors often push their half-eldar charges to reject a full half of themselves in order to "better" themselves.
Theramore Confederacy
Before the Theramore Confederacy existed there was an Eldar Exodite world called Daltarias. Having narrowly escaped the Fall the Eldar living there were having a difficult time adjusting to their new life. Centuries later, a colony ship sent from Mars crash-landed on the surface of Daltarias. Angered by this apparent intrusion into their territory, the Eldar began to kill the survivors of the crash. The remaining colonists fled, and lived lives of solidarity in the vast jungles of the world. Even though they fled the Eldar still perused them, picking them off one by one. A powerful and influential man known as Chemlost the Redeemer sought to end the slaughtering of his kinsmen by the Eldar and gathered the remaining colonists. These remaining people were toughened by years of hiding from the ever persistent Eldar and were either experienced soldiers or powerful psykers. Slowly but surely they muster enough strength to oppose that of the Eldar. Fierce fighting started, and many fell on both sides. Suddenly, during the middle of the war, a large warp-storm opened up around Daltarias and the surrounding systems. Slowly, the storm divided into many smaller ones, surrounding Daltarias and numerous other systems. Daemons poured from the rifts in space, crushing the humans and Eldar one by one. With no choice, the Eldar and Humans made a temporary cease-fire until the daemons had been banished. After the daemons were beaten back to their own realm, many humans and Eldar had made bonds of friendship from fighting side-by-side for so many years. At first the races lived in peace, but separately. Slowly but surely, the races began to interbreed and created a race of half-human half-Eldar beings. Eventually, these beings colonized the 13 systems within the confines of the warp-storms and began seeking a way to leave the cage of their own making.
Great Crusade
As the Emperor was conducting the Great Crusade, the Theramorians (as they began calling themselves) had finally used webway gate that allows them to escape the Cage without being sucked into the warp forever. But before the new system could be tested the Emperor had found a way into the Theramore Confederacy. Before long, the Theramorian fleet and the Emperor's crusade fleet began attacking each other. Suddenly, the Emperor had found him trapped within the network of the warp storms that surrounded the confederacy. Realizing this as a good chance to make peace with the crusade fleet, the Theramorians offered to give them the webway gate to escape the cage of warp-storms and in exchange the Imperium would leave them alone. As the opposing forces met on a neutral asteroid, both sides were shocked by the fact that both factions were almost genetically the same. Being slightly taller than the average human, the Theramorians blamed this mutation on the low gravity of the worlds they inhabited. The negotiator sent to make peace wisely kept their mouths shut about their half-Eldar blood. Since all of the battles had been ship-to-ship they had never met face-to-face before. The Theramorians decided to change their deal with the Imperium. They would join the Imperium, but will be able to make their own laws and taxes in exchange the Theramorians would give the Imperium address of webway gate and the Imperium would give them the plans for creating Rhino STC's to aid in their defense from other xenos species. As their trust built up, the Imperium slowly gave into the persuasiveness of the Theramorians and eventually acknowledged the requests made by them.
The Gullieman Hersey
When news of the Gullieman 's rebellion reached the Conferderacy, they did as much as possible to reinforce their worlds and the warp storms surrounding them. They had realized these systems would be a good fortress for any chaos followers. Easy access to the warp, far away from Imperial forces and nearly impossible to penetrate. As the Theramorians predicted, the forces of chaos poured into the confederacy, slaying at will. Before the attack could be halted, an entire system had been lost. If it were not for the timely intervention of the Luna wolfs the Confederacy would have been taken by chaos. Poorly positioned to help in the war at all, the Guardsmen (called the Scarlet Militia by the locals) were ordered to prevent any subsequent attacks from getting through. In the times since the Hersey chaos has attempted many times to take the Confederacy for their own.
The Third Founding
After the First and Second foundings had occurred the Imperium decided to honor the Confederacy with a Space Marine chapter of their own. Dubbed the Red Guard they were assigned the task of defending the cage from Chaos and keeping Eldar raiders out of the Imperium. The gene-seed for this new chapter was drawn from the Thousand sons. The new Red Guard did their job efficiently and effectively, and many a Chaos incursion or the Dark Eldar raid had been hatled at the worlds surrounded by the Cage. Now an extremely decorated chapter, the Red Guard was honored by the Imperium and being recruited was to be a blessing on the new recruit and his family. Despite this prestige, the Inquisition forever kept their eyes on the Red Guard and the Confederacy as the amount of freedom they enjoyed was worrisome to them.
The Break
In early M34 while analyzing the DNA within one of their recruits, the Red Guard discovered he was not entirely human, the man was a portion Eldar. Simply dismissing it as a simple mistake, the Red Guard ignored this fact and proceeded to induct the man into the Red Guard. But soon enough more and more Red Guards began to show up with mixed Eldar DNA, fearing the worst, the Red Guard began to stop giving their gene-seed tithes to the Imperium fearing they would be purged. Using their authority within the Theramorian Confederacy, they forced the systems to stop sending planetary tithes as well. The Inquisition soon discovered the Confederacy had been withholding their planetary tithes and the Red Guard had withheld their gene-seed tithes, Launching an official inquiry, the Imperium sent an Inquisitor and his men to find out what happened. They never returned. Suspecting heresy, the Imperium sends a larger Inquisatoral force to the planet, and placed their father Chapter, the Thousand sons, to watch over the Red Guard. The Inquisitor forcibly took gene-seed from the vastly bloated stocks from the fortress-monastery and sent them into the Adeptus Mechanicus for analysis. The Mechanicus isolated the rogue genes, but was also able to identify them as eldars. After much debate in terra it was decided that Theramorians and Red Guard will be given one chance to have this Hersey absolved, they will be given Abhuman status (Homo sapiens diutinus), if any Theramorian ever try to rebel then they will be declared heretics and excommunicate traitoris. Red Guard will take part in a hundred year long Crusade as an act of penance for failure and incurring the displeasure of the Emperor. It was decided because they are an extremely decorated chapter for this reason alone, they are only given this one chance, so that Chapter earns the forgiveness of the Emperor thus allowing the Space Marines to return to their homeworld and be absolved of heresy. Their Chapter Master, Khoisan Neotera, was stripped of his honor and armor, and imprisoned in Penitentiacon in isolation for the rest of his life. As part of this penitent crusade their homeworld, Theramore, was forfeited to the Blood Raven Chapter, which had taken part as loyalists in the war. This meant that for the duration of the crusade the Red Guard would be forbidden to recruit new members, and as of the end of M34 they are critically short of personnel. Over eight decades into their century-long Penitent Crusade and having battled relentlessly across the vast swathes of the Imperium and beyond, the Red Guard Chapter came upon the ruins of the Orpheus Sector. Discovering a realm decimated by war, the bones of countless heroes being picked over by the verminous Necron Xenos, the Red Guards vowed that their death quest will be completed upon the battlefields of Orpheus. Unheralded, the Imperial task force assigned to track the Red Guards on their Crusade arrived in the region, several days later, and a series of high level astropathic transmissions were directed at Terra and the Inquisitorial Representative on the Senatorum Imperialis. For their deeds They are no longer banned from recruiting Neophytes by the Inquisition, because of their actions, their homeworld was given back and they were absolved. Now Theramore has the largest population of half-eldars anywhere in the Milky way.