Board Thread:Questions and Answers/@comment-99.234.104.217-20160405215649/@comment-24045678-20160406035015

Officially, the two universe are completely seperate....however writers from Games Workshop (the people who made both franchises) have often hinted that the two universe are connected indirectly in several instances, though no official response of whether this is official is true as of yet..

Example 1: In the book "End Times: Thanqoul", the Skaven discovered an ancient communication device hidden within an ancient Temple City. The beings that they've accidentally talked to in the machine were "hinted" to be the Eldar from Warhammer 40k due to the "elvish" yet alien tone of hte speech....again no confirmation, simply a very likely theory....

Example 2: When the two Wood Elves Araloth and some other Female Elf went into the Gardens of Nurgle to rescue Shaylla from Nurgle's imprisonment, they met up with a giant Silver Knight with a wierd tone.....if you've read into Grey Knights Codex, this is HEAVILY hinted to be Kaldor Draigo from 40k lore

This are just a couple but If I had time I could've added more instances...