Valhalla - History: The harsh Ice World of Valhalla was originally a verdant Paradise World. No records survive of its colonisation by Humanity, but Valhallan legends recall a world ripe for conquest.Unfortunately, Valhalla was destined for catastrophe. Approximately ten thousand standard years ago, just before the end of the Age of Strife, a rogue comet entered into a collision course with Valhalla.The planet's defence lasers fired at the comet, but only succeeded in breaking it up. Later, it was found that the comet was made of almost pure iron, explaining why the large defence lasers had proved so ineffective.The comet impacted in Valhalla's vast planetary ocean, but a mile-wide fragment struck the northern continent, creating vast plumes of dust which proceeded to cover the planet in a blanket of dirt. To make matters worse, the planet's orbit was altered by the ferocity of the impact, moving it on a course that forced it into a new orbit farther from its sun.This change in the amount of incoming warmth and light altered Valhalla's ecosystem permanently, reshaping the planet into an icy wasteland. The Valhallan people struggled to survive in this new environment, fearing famine due to a lack of viable farmland, until they carved out new homes for themselves in massive subterranean caverns deep beneath the ice.The comet strike had been a castastrophe, but was not to be the end of the Valhallan people's suffering. Not long after the comet strike, a damaged Ork warfleet descended on the world and proceeded to fight the Valhallans for every gram of the precious food they had stored.The Valhallans held out bravely for a long time in their vast hive cities beneath the ice but were ultimately pushed back to the food vats. Eventually they destroyed the Orks by using ice boring machines to strategically strike at the heart of the mob, burning and melting most of the Orks and scattering the rest.Even this Greenskin invasion proved unable to blunt the Valhallans' indomitable spirit. Their grim refusal to surrender, despite overwhelming opposition, had won them a historic, if bloody victory.After destroying the Ork invaders on their own world, Valhallan Planetary Defence Forces regiments, in an act of vengeance, joined with other Astra Militarum armies to cleanse their sector of the hated Greenskin menace.The Imperial Guard proved so impressed with the combat ability of the Valhallans that the Departmento Munitorum soon turned to Valhalla as a prime source of new Astra Militarum regiments. After being raised as Imperial Guardsmen themselves, the Valhallans continued to display the same stoic determination that they had shown in defence of the ice-cities of their own homeworld.To this day, the courage and tenacity of the Valhallans in battle continue to earn them the respect and admiration of other regiments from all over the galaxy.A stubborn and stern people, Valhallans refuse to acknowledge their own hardships. They are all but impervious to harsh conditions and have a casual disregard for Human life.Due to the overcrowded conditions within the subterranean habitats on Valhalla, life is considered cheap. Even the most petty crime carries with it the harshest of sentences: death.Those who do not serve in the local Valhallan military or volunteer to join the Imperial Guard must toil in the dark caverns, cultivating the nutrient slimes that sustain the populace.Valhallan soldiers are expected to carry each and every item they will need to survive. Without their thermally insulated greatcoats and helmets, a Valhallan Guardsman's blood would freeze within seconds on the arctic surface of Valhalla.The armoured battle tanks and artillery units of Valhalla are uniformly camouflaged in a manner suited to the frozen tundra of their world, and each vehicle proudly displays the name of their homeworld on its hull.It is common for regiments of Valhallans to be assigned by the Imperial Guard to planets infested with Orks due to their intimate knowledge of Ork tactics and their dogged determination in the face of defeat, where other armies might run.