This is a really hard decision for me. Let's see:
Norway:
Emperor, Darkthrone, Mayhem, Satyricon, Burzum, Theatre of Tragedy, Tristania, Arcturus, Ulver, Borknagar etc.
Sweden:
Katatonia, Bathory, Dissection, At the Gates, Opeth, In Flames, Dark Tranquillity etc.
I'll go with Norway.