In the Arms of My Enemy 2007 on netflix

Jakub and Vladimir, two brothers in their late teens, join in the Cossack army to flee poverty. Elias and Roman, two other brothers, on their own as well, steal horses to survive… When fate brings them together, the encounter proves lethal. Vladimir gets killed. Jakub now burning with anger, is obsessed with revenge. A wild track begins, no one will be left unharmed…