In the Great War Against Chaos, the entire army of Kislev was wiped out, as was just about every defender of Praag. The defenders of Kislev City took ruinous casualties. The only Kislevites that got through it relatively untouched were the ones that, when Chaos came knocking, did not join the army, did not defend the city in the path of Chaos, and did not defend the capital of Kislev - instead, they defended the city furthest away from Asavar Kul's invasion path with easy escape routes into Ostland or the Sea of Claws. Pretty much every patriot, every true believer, anyone with courage and conviction in Kislev placed themselves in the path of Chaos and most of them died as a result, and in the aftermath the cowards greatly outnumbered the lucky. A lot of Kislevites blame the downturn in just about every Kislevite institution since then as much on the lack of character of those who survived as they do on the damage done by the Great War, and this lack of trust in the leadership of Kislevite institutions is what allowed the Gods of the Empire to get a foothold in Kislev.
In the aftermath of the Great War that Kislev is still languishing in, there is no more Fire Spire magic, and no Dazh or Tor or Ursun Priests that are seen as brave and trustworthy. Only the Ice Witches were left relatively intact in population and reputation by the Great War, because the Ice Witches rallied to Kislev City instead of Praag because of their long-standing and well-known hostility towards the Fire Spire.
