The Guns of Fort Petticoat (1957)

Opposing his commanding officer's decision to attack a group of innocent Indians and wipe them out, Lt. Frank Hewitt leaves his post and heads home to Texas. He knows that the attack will send all of the tribes on the warpath and he wants to forewarn everyone. He gets a chilly reception back home however. With most of the men away having enlisted in the Confederate army Frank, a Union officer, is seen by the local women as a traitor. He convinces them of the danger that lies ahead and trains them to repel the attack that will eventually come.