Ancient History:
It might come as a surprise to many that while the Chaos Dwarfs as they were presented in Warhammer 4th edition were an entirely fresh take on the concept, many of the individual elements and details of the Chaos Dwarf background were based on early Warhammer material.
Case in point, this page from the Autumn 1985 Citadel Journal, provided courtesy of Stuff of Legends, and introducing Black Orcs. From the very beginning, you can see the plot elements that Rick Priestley would later pick up, particularly the Black Orcs’ “unnatural origins.”