Black Metal emerged in Scandinavia in the early '90s. Inspired by the overt, fantastic paganism and Satanism of Venom, Celtic Frost, and Mercyful Fate, Norwegian and Swedish bands Emperor, Dark Throne, and Mayhem changed Death Metal. Though still driven by speedy blast beats, these bands had less bass and sounded more metallic. Their imagery became more gothic and their music became more dramatic. Vocalists mixed the Death Metal growl with high-pitched screaming and song structures became more elaborate. Cradle of Filth and Dimmu Borgir created the musical equivalent of the campy Hammer Studio horror films, revolving around lust, vampires and ancient legend, often incorporating operatic female vocals and lush keyboards. The nationalist tendencies of bands such as Enslaved and Immortal have evolved into Viking Metal, based in the ancient lore of Scandinavia.