Well, contrary to what most believe, war hasn't really changed all that since WW2, its still the same gritty, ugly, nasty mess, no matter what the 'heroic soldier' propaganda says. Hard to tell from the film if they show all Russians or some Chechen fighters but its all the same really.
Yea, Chechnya - the Russians really messed up there, for sure. Made a *relatively* peaceful and modern nation into the incarnation of Hell On Earth. Just because they couldn't take losing another republic, Yeltsin was too drunk to give a sh*t, and the generals wanted a war badly, to show the russian army was still mighty.
So they went in to get the 'black bandits', which totally failed of course, as the first Chechen war was a total disaster for the russian army. And Checnya got turned into a training ground for the Jihadists... way to go Russia.