Fort Courageous.

In this western, a cavalry sergeant is wrongly court-martialed. To reclaim his good name, he takes over a patrol that just lost its leader in an Indian attack. He leads the regiment to Fort Courageous, but is appalled to discover that the Indians attacked and massacred all but one of its inhabitants. The hardy little group must now fight the renegades on their own. The ex-sergeant plans a brilliant strategy that culminates in winning the Indian's respect. They leave the fort alone and peace is restored.