In case you've come upon this movie by accident, I'd suggest you go ahead and watch it, and then return return back to read the reviews.
The Brest Fortress pushes war movies to a completely different level of realism, poetry and emotional force. It is so visceral, so real and so emotionally powerful that by the end you're part of the battle and no longer a detached viewer. Not a single shot is wasted, not a single line of dialog is a filler, not a single acting even from extras feels like acting, not a single moment do you feel that this is a movie and not real life. The makeup, the wounds, the dirt, the blood, everything is real and it all hits you with one of the best cinematography in a war movie since Ivan's Childhood. And The Brest Fortress pays homage to that great movie in many ways.
Russians suffered unimaginable horrors during WWII and that trauma in their psyche along with their great heritage of story telling and great cinema combines to create another great Russian war movie.
I feel privileged to have watched this movie, knowing that its still unknown in the west, there is not even a wikki page about it yet.