[yawgmoth]

While I Bathory was a big influence for a lot of bands, Possessed and Death were both producing rehearsal tapes and demo tapes in '84. Hellhammer (of Switzerland) was arguably more important with their Satanic Rites demo, in '83 [1]. Note I'm not disagreeing with you, just discussing degrees of influence. Bathory's influence would be much more important in the first and second wave of black metal.

[1] http://www.metal-archives.com/albums/Hellhammer/Satanic_Rite...

[amerika_blog]

I generally cite the triad as thus: Bathory, Hellhammer and Slayer, all of which had releases in the 1983-1984 period. Sodom is also important. Death, less so, since its demo at that point sounded more like speed metal (it was only after the time spent with Repulsion, formerly Genocide, that Chuck hit on the death metal formula). If we're into the 1984-85 period with Possessed, we also need to include Sepultura, Master/Deathstrike, and Morbid Angel.

[yawgmoth]

I wasn't aware of the Repulsion/Death bits. Awesome!