Drastus, Hexenkreis and Glorior Belli are some of the big names to be in the French BM scene. But there's so many...
Don't think I've seen Ancalagon or Himinbjorg in this thread so far, now these play some kickass epic viking metal if I ever heard some.
Otherwise I would second most recommendations by Abruptum and MadeInNewJersey.
Oh, and you can't live without Deathspell Omega, believe me...