I had to go with Canada just for the old thrash scene. Razor, Infernäl Mäjesty, Voivod, Slaughter, Obliveon, Exciter, Sacrifice, etc.
This^ too.
Voivod are easily one of my all time favourites.
Plus there is Thor, Thunder Rider, Voor, Sacred Blade, Overlord, Outbreak (that Nazi-thrash band), Dahmer, Witches Hammer, Bastardator, Inepsy, Iron Dogs, Ice War, Chapel, Fornication, Occult Burial, Funeral Circle, Gatekeeper, Tales Of Medusa, Cromlech, Dark Covenant, Sweet Torment, Gatrekrashor, Barrow Wight, Possessed Steel, Cauchemar, Necroholocaust, Hrom, Ezra Brooks, Messiah Force, Damnation (1980's), Piledriver, Armoros, Dissection (thrash), DBC, Cryptopsy, Sacramentary Abolishment, Weapon, AMSG, Kataklysm, Morbid Decapitation, Putrescence, Gyibaaw.
Yeah, Canada fucking slays.