The film is considered a Western take on The Mutiny on the Bounty. The relationship between Tom Dunson and Matt Garth is deeply complex. Although they’re prepared to kill each other, deep down they still respect for one another. This relationship is based on control, idealism, respect, and trust.
 Wayne and Clift play beautifully off against each other. Father and surrogate son, first working together and then having a big difference of opinion on the cattle drive. Clift started a film career in Red River playing sensitive people who you can only trod on just so long before they take action.
 If anyone doubts John Wayne as an actor of note then they need look no further than his performance here as Dunson. Tough and durable in essence the character is, but Wayne manages to fuse those traits with a believable earthy determination that layers the character perfectly. With Wayne all the way, matching him stride for stride, is Montgomery Clift as Matthew Garth, sensitive without being overly so, it’s the perfect foil to Wayne’s machismo showing. Walter Brennan and John Ireland also shine bright in support, while a special mention has to go to a wonderful turn from Joanne Dru as Tess Millay…
-Excerpts from IMDB reviews
Fourteen years after starting his cattle ranch in Texas, Thomas Dunson (John Wayne) is ready to drive his 10,000 head of cattle to market (1,000 mi. away in Missouri). Back then Dunson, his sidekick Nadine Groot (veteran character actor Walter Brennan) and a teenage boy, Matthew Garth (an orphan/survivor of an Indian attack on a wagon train) started off with only two head of cattle. Dunson is a harsh task master, demanding a great deal from the men signed up for the drive. Matt is a grown man now (who fought in the Civil War); he has his own mind and soon runs up against Dunson who won’t listen to advice from anyone. One of the drovers, Cherry Valance (John Ireland), proposes that they head toward Abilene. When the cattle stampede, Dunson goes to “gun-whip” one of the hands, but Matt intervenes. The men start taking sides and Matt ends up in charge w/ Dunson vowing to kill him. In the scene where Clift tells him he’s taking over the drive, Wayne turned his back on him and said in a low voice, “I’m gonna kill you, Matt.” This went against director Howard Hawks’ idea to have Wayne cringe, but the actor refused to appear cowardly and played it his way. The improvised moment left Clift astonished, but Hawks liked it (and it was used in the final cut).
Bet I ate ten pounds in the last sixteen days. Before this shenanigan is over, I’ll probably eat enough land to incorporate me in the Union. The state of Groot. -Groot complains (re: traveling through dirt roads)
You’re fast with that gun, Matt. Awful fast. But your heart’s soft. Too soft. Might get you hurt some day. -Cherry comments / Could be. I wouldn’t count on it. -Matt replies
There are only two things more beautiful than a good gun: a Swiss watch or a woman from anywhere. Ever had a good… Swiss watch? –Cherry jokes w/ Matt
This is the kind of Western for the classic movie fan who avoids (or doesn’t usually enjoy) the Western genre! After seeing Wayne’s performance, rival director John Ford commented to Hawks: “I never knew the big son of a bitch could act.” This led to Ford casting Wayne in more complex/multi-layered roles, incl. The Searchers (1956), and The Man Who Shot Liberty Valance (1962). Hawks originally offered the role of Dunson to Gary Cooper, but he declined it (b/c he didn’t believe the ruthless nature of the character would’ve suited his screen image). This was the debut of Clift (26 y.o. during filming and looking gorgeous), who was known as a talented theater actor. He learned to ride horses while at military prep school, but that was a different kind of riding than this role. Hawks always had high praise for how hard Clift worked (on his cowboy skills) for this picture. After seeing the final version of Red River, Clift found his performance mediocre, but recognized it as a star-making role. He later said: “I watched myself in Red River and knew I was going to be famous, so I decided I would get drunk anonymously one last time.” Burt Lancaster (a former acrobat) was first offered the role of Matt, but he had already signed on to star in the iconic film noir, The Killers (1946), which was his debut.
There was concern that the leads (Wayne and Clift) would’t get along, since they were opposed on all political issues and both were outspoken on their views. The actors agreed not to discuss politics during shooting. Clift sometimes joined Wayne and Hawks in the nightly poker games they organized. Clift later said: “They tried to draw me into their circle, but I couldn’t go along with them. The machismo thing repelled me b/c it seemed so forced and unnecessary.” In Life Magazine, Wayne described Clift as “an arrogant little bastard.”