I don’t believe a Death Eater can be forced to take the mark under Imperius.
i buy not being able to cast the 3 unforgivables under the imperius but can't take the mark? it depends on the nature of the mark and how it's applied which from what i recall is never clearly described in canon
Author's response
Hello goku.
And there is the crux of the matter. Rowling never said what is needed to take the mark. We only know that he can summon and punish his servants, he can track them (Karkaroff), and it hurts…a lot (Wormtail and Draco). Everything else is fanon. However, barring any conflicting information, I believe my argument is still valid. If the mark is tied to the soul, or the magic, it would take something as ugly as Dumbledore’s description of creating a horcrux to form that bond. I have to believe that that requires conscious thought.
Alorkin