The Last Frontier is a 1955 American Western film directed by Anthony Mann and starring Victor Mature, Guy Madison, Robert Preston, and Anne Bancroft.

During the American Civil War, fur trappers Jed Cooper, Gus and Mungo are returning from a trapping expedition with a load of furs when they are surrounded by a large party of Indians, who ask them to hand over their guns, which they do.

The Indian chief, Red Cloud, tells them they must leave the land and not return, if they do they will be killed.

At Jed's insistence, they head to the fort to get compensation for the stolen skins, though Gus would rather go to Canada, as he doesn't think that soldiers can be trusted.

When Jed asks for compensation for all their losses, Riordan offers to recruit the three men as scouts, to which they all, eventually, agree.

With their first pay in advance they get drunk, and Jed bursts in on Corrina Marston, asking for more whiskey.

With some of the men urgently in need of a doctor, Marston finally relents and they proceed to Fort Shallan.

He is not happy with the posting, feeling that there is little chance to achieve the glory that is missing from his career.

Rioran explains that his orders are to hold the fort, and that his men are mostly raw recruits.

Jed discovers that Red Cloud is gathering a large force of allies and reports to Riordan in the hospital.

The fort's doctor, Captain Clarke, who is on first name terms with Marston, tells Riordan to stop him.

While Marston is addressing the men as they are about to leave the fort, a drunken Jed bursts through the ranks and shouts that they are all going to get killed.

Sgt Dekker tells Marston that Jed's outburst has unsettled the men.

After a long fight, which ends in front of the officers and men, Dekker falls off a roof and is killed.

Jed jumps out of the fort, and as he runs away Riordan aims his pistol at him, but does not fire, even though Marston orders him to.

When he doesn't, Riordan places him under arrest, on the authority he expects to get from Fort Laramie.

Jed finds Red Cloud's war party waiting to ambush Marston's troops.

As the foot soldiers follow the cavalry, Jed runs up and tells them to stay in the trees.

[4] The role was eventually given to Victor Mature who had just signed a two-picture deal with Columbia.

[5] Filming was to have started in January 1955 but this was pushed back, in part so Mature could make Violent Saturday.

[7] Yordan says he rewrote the film coming up with the theme that the Mature character wanted to get into the army so he could woo a woman.