Board Thread:General Discussion/@comment-11276487-20130713025241/@comment-12599067-20130801140453

Oh, yeah. Forgot about Sovngarde. My point being, he's never truly defeated. It seems to work something like how Daedra can't be truly defeated in the mortal realm. So it's safe to assume Alduin is floating around Aetherius, or the Void, depending on your beliefs.