There was a Mordheim annual, and Empire in Flames supplements for Mordheim, plus all the Town Cryer magazines. There also used to be GW comics, Inferno was one of them. They had short stories, and comic stories. Ulli and Marquand. Across those, if you can find them, there may be snippets of info for the Empire at that time, though my memory of it was that it wasn't much different to the Karl-Franz era
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