User blog comment:Squeaky the first/Warhammer and Warhammer 40K, relations./@comment-1932673-20111209154310

I believe that the two are separate universes as 1. Magic and Warp Powers seem to function differently and seem to come from different sources regardless of any similarities and 2. the sheer amount of magic in fantasy warhammer would give it away to any faction with psychic capabilities and 3. The technological and cultural differences between the Elves and the Eldar can't be explained by the elves being advanced Exodites who have forgotten their heritage as the warhammer planet being in the 40k galaxy would imply.