The 13th Warrior (1999)

Plot:

In AD 922, an important emissary who is banished from his homeland. The nomadic outcast comes across a band of Norse warriors who coerce him into joining them when they are summoned to fight mysterious creatures legendary for consuming every living thing in their path. Eventually surrounded by the frightening and ferocious foe, Ibn must conquer his personal fears and help battle the illusive invaders--who emerge out of the shroud of fog in the black of the night.