The planet of Valhalla lies in the dense layer of stars in the heart of the the Ultima Segmentum. Millennia ago the planet was a thriving and lush world, with broad wide oceans separating the vast polar continents a world known as a paradise planet, far from the dangers of the rest of the galaxy. All of this was destroyed in an instant.

One night the people of Valhalla saw an ominus new star in the sky, it was a comet made of almost pure Iron, blast after blast of laser energy was fired into the thing but nothing made a dent in the vast mound of rock. The planet gave into to despair until the comet hit, a chunk a mile wide splitting from the main meteor and devastating the northern continent and spraying dust far into the atmosphere. The main body of the comet struck deep into the middle of the seas striking with enough force to knock the planet a further 6 million miles from its sun.

When Valhalla came to a rest it was a very different planet, the ice spread from the seas and the water and dust in the atmosphere blocked all light from the planet, almost every native life form died out and the people clung desperately to the last shreds of land until at last these disappeared under the ice. Valhalla had become an Ice World, its people living in tunnels in the kilometre thick ice. After months of cannibalism and starvation, hope was restored when a nutrious algae broth was created, enough to feed the cold bodies now hunkered in the cold tunnels.

The Valhallans thought that fate had finished with them, it had not. In a final cruel twist a damaged fleet of Ork ships crashed on the planet. Virtually immune to the cold the Orks launched a devastating attack on the Ice holes and shelters of the Valhallans, who fell back under the fury of the greenskin assault again and again until finally there spirits snapped. The Valhallans fought with a passion and the war grew ever more vicious, tunnels collapsed and every inch of ground paid for in the blood of both sides. The tales of courage in this struggle would and have filled volumes, needless to say the Valhallans eventually won, a last desperate struggle in the food processing plant spelling beginning of the end of the Ork threat. The struggle left an indelible mark on the Valhallans soul, a sense of bitter irony resolute defiance has been etched on every inhabitant since.

Valhalla is now a world of eternal winter, kilometre thick ice covers the surface while bitter storms whirl across the planet and scour the snows clean. Its people live under the skin of the world in vast frozen caverns. Huddled together for warmth from the ever present cold. Venturing up to hunt the few creatures that have adapted to the cold and harvest the bitter Tanna leaves that thrive on the ice. Despite this Valhallans are still fiercely proud of both themselves and their homeworld and are utterly at home amidst the ice and snow.

Use the Imperial World as a starting template, replacing the Blessed Ignorance and Liturgical Familairty traits with the following

Kings of Ice
The children of Valhalla are taken to its icy surface and taught the mystery of survival on the Ice almost from the time they can walk. Parents and Grandparents consider it a duty to inure their offspring against the harsh climate of the world.
Benefit - Valhallans treat Navigation and Survival as basic skills, gaining a +10 bonus in icy conditions. However Valhallans are not at all used to the warmth of even a temperate world and all tests will be at –5 in tropical or desert enviroments. With fellowship suffering a –10 modifier as the Valhallans sweats and curses in the infernal heat

Ancient Grudge
Growing up on Valhalla the children are told stories through the long nights of the evil of the Orks, of how they came and struck the Valhallans in their most desperate hour. Every child of the snows fosters a deep grudge against the greenskin menace and they make some of the best Ork hunters in the Imperium
Benefit – Valhallan characters gain the Hatred (Orks) talent