A certain irreverence toward the western may have hurt Cagney with contemporary audiences
As a western, it's an archetypal town-tamer story that looks forward to the sort of reluctant-hero roles Bogart would play when he got the chance. Here Bogart (as the purply-named Whip McCord) leads a gang of gamblers and bandits who are robbed by Cagney after they rob a stage. The Oklahoma Kid -- no one knows him by any other name -- has returned to his native ground to witness the famous Land Rush. Like both versions of Cimarron, Kid makes the blunder of staging this tremendous action scene -- though the action here admittedly isn't so tremendous -- very early in the picture. Bogart's gang are "Sooners" who've jumped the claim of the patriarchal John Kincaid, who'd planned to build a town there. Bogart promptly surrenders his claim, however, on the condition that Kincaid cede him exclusive gambling rights in the new town. Meanwhile, the Kid has sat out the land rush in a saloon, explaining to whoever has time to listen that the whole enterprise is futile. Those who play by the rules now will lose out to the strong, he says, and the strong will lose out to the clever in the end. He has to flee to Mexico after killing one of Bogart's men, and once he returns the town is booming but in ways Kincaid never wanted. The old man's accommodation with Whip McCord can't last much longer, despite the good faith efforts of Judge Hardwick (Donald Crisp), his daughter Jane (Rosemary Lane) and Hardwick's law partner Alec Martin (Charles Middleton in a good-guy role). Bogart concocts a plan to frame Kincaid for murder, trick Hardwick into leaving town, and have his judicial pawn railroad Kincaid to the gallows. Despite the efforts of Jane and the Kid, who has finally let on that he's John Kincaid's black-sheep son, the old man is lynched, hung from a second-story porch. This would seem to prove the Kid's earlier point, but now that it's personal he's not so complacent.
Cagney is Cagney here, and if you can't see him as a westerner I can't help you with this film. There are plenty of characteristic moments, from his forcing a saloon pianist to play "I Don't Want to Play in Your Yard" at gunpoint to his showoff singing of "Rockabye Baby" in Spanish. Oklahoma Kid isn't a great western by any stretch, but it's no more a category error than Frisco Kid was, and as a Cagney vehicle it's perfectly acceptable. Bogart gives his stock 1938-40 villain performance and if you've seen one of those you've really seen them all. He'd return to westerns well before Cagney did, stuck between Flynn and Randolph Scott in Virginia City, but the closest he came to the genre after achieving real stardom was the modern-dress Treasure of the Sierra Madre. Bacon directs competently but you can't quite shake a feeling that, despite Cagney, Warners considered this a second-class project compared to Dodge City, the latter getting Technicolor while Kid goes without. The idea that Kid is a second-class western, at most, may have started right there, but while it really is a second-class western, it could be a lot worse, and it's actually a lot better than its dire reputation -- built perhaps on sight-unseen judgments -- would suggest.