Originally Posted by http://en.wikipedia.org/wiki/Death_metal

Emergence and early history
English heavy metal band Venom, from Newcastle, crystallized the elements of what later became known as thrash metal, death metal and black metal, with their 1981 album Welcome to Hell.[14] Their dark, blistering sound, harsh vocals, and macabre, proudly Satanic imagery proved a major inspiration for extreme metal bands.[15] Another highly influential band, Slayer, formed in 1981. Although the band was a thrash metal act, Slayer's music was more violent than their thrash contemporaries Metallica, Megadeth and Exodus.[16] Their breakneck speed and instrumental prowess combined with lyrics about death, violence, war and Satanism won Slayer a rabid cult following.[17] According to Allmusic, Slayer's third album Reign in Blood "inspired the entire death metal genre".[18] It had a big impact on the genre leaders.[16]