Random? musings on a topic that comes up in discussion from time to time...
I enjoy military history and world-building, and as such I am acutely aware of the major issue in the Warhammer world - that of how Chaos manages to muster vast armies and throw them at the Empire, which seems to be consistently outnumbered and overmatched time and again. On the basis of geography, population density, and distance alone, it seems like such a campaign would be destined to failure before it ever began. There is simply no way that Archaon can keep 100,000 northmen together for any length of time - his army would eat itself out of its own camp in a matter of days.
But there may be a way!
To my mind, the best way to map the north is to consider a piece of paper on a table. The paper represents a normal region of the world - stable, consistent, measured. But what happens if you push the ends of the paper together? It rolls up like a wave. It occupies less space on the table...yet the paper has the same surface area. This effect could be considered to grow as one approaches the Polar Vortices. In this way, the north is vast - much, much larger than a map reflects, and much larger than the men of the south can really comprehend.
But by the same token, the distance between two points on the paper can now be measured in two ways - one by measuring across the surface of the paper, up and down the waves; and the other by measuring from point to point in space. And there are ways to travel the second way, understood by ritual or rote by the men of the north - for example, sacrificing blood upon the altar of Karamsun may open the Chiragan Pass, allowing travel to the green lands beyond in a matter of days; without the Pass, one must hike over the Giantsgorge Mountains, a journey that takes over a year. The northmen don't know why the blood on the altar makes a difference, and they don't recognize that the Pass is, in effect, a magical portal that appears as the landscape they live in - but they do know that it works.
And as the Winds of Chaos grow from the north, the edges of the page condense further, and the point-to-point gaps become larger, more frequent, and more stable. In this way, the men of the north have, in effect, access to much more of the north for hunting, gathering, scavenging, and pillaging as they prepare for their great wars. They have less distance to travel to muster, and more direct access to home before they go. They wouldn't think of it as odd, but the mustering would be not only an act of mortals but an act of the gods, condensing their very world so as to compel the concentration of forces.
The concept is entirely open to further exploration, of course; perhaps there are vast kingdoms and empires unseen by any southern eye; maybe time moves more slowly higher up the crests, so that the warriors who invade the Empire are led by living veterans of the last war, 300 years ago; and perhaps the effect of strong faith in Sigmar is like a paperweight, crushing down the crests and flattening the world, limiting the northmen to the physical rules that the south lives by.
Just my musings, and I'm sure there are logical flaws in there. Thoughts?