Rancher writ large. Instead of owning one regular-sized ranch, the Cattle Baron will own several ranches, possibly in more than one state, or a county-sized one with many thousand head of cattle. He (or very rarely she) will be one of the wealthiest people in the territory or state, and one of the biggest employers.
A Cattle Baron is generally at least middle-aged—it takes a while to accumulate that much capital. Some will be homegrown types who struggled their way up from single ranches, while others are foreigners (English and German are popular nationalities for this) who simply bought up land. Their clothing, tack and homes will tend to be rather ostentatious, but somewhat practical for range life.
Cattle Barons in fiction will usually have either grown or nearly grown children, a beautiful daughter and/or either a rebellious or dutiful son. Conflicts between the children, and with their parents, are frequent.
In The Western, a Cattle Baron will often be the Big Bad of the story, (Aristocrats Are Evil, even if the "Baron" bit is metaphorical with "Robber Baron") with the desire to buy out or crush independent ranchers and homesteaders to add to his wealth and power. However, they can also be a benign employer for a protagonist if their holdings are plagued by rustlers. Expect them to be rather autocratic in any case.
- Patrick Stewart's character in The King Of Texas, a Western version of King Lear.
- Spencer Tracy's character in Broken Lance, also a western version of King Lear.
- John Wayne's characters in Red River and Chisum.
- Alan Rickman's character in Quigley Down Under is an Australian take on the type.
- A variation on this is John Huston's character in Chinatown, a Land Baron.
- John Chisum was an actual Cattle Baron during the 1870s/1880s. He was portrayed by John Wayne in Chisum and James Coburn in Young Guns II.
- Parodied by Andy Griffith in the film Rustlers' Rhapsody; the narrator notes how you never actually see any of his cattle, just hear them mooing occasionally in the background.
- J.W. Grant (Ralph Bellamy) in The Professionals. He thinks his money can buy him anything.
- 'King' Carney and Neil Fletcher in Baz Luhrmann's Australia. Sarah Ashley's late husband Maitland is a cattle baron of the foreign-born variety.
- The eponymous character of McLintock! is the Benevolent Boss variant. He started out as a rancher and worked long and hard so his wife and daughter would prosper. He uses his considerable influence to resist the machinations of an Obstructive Bureaucrat and stand up for the local Comanche.
- In Forty Guns, Jessica Drummond is the most powerful rancher in Arizona territory, and controls much of the territory's government.
- The last story in Grim Prairie Tales has Horn, the richest man in the territory, who is holding a contest for the position of being his new hired gun. Rich enough that he rolls right over the objections of The Sheriff that what he is doing is tantamount to murder.
- In Curse of the Undead, Buffer runs the biggest ranch in the district, and he is trying to drive out his neighbours so that he can add their land to his spread.
- The protagonist's dead sister's husband, James, in Sisters by Lynn Cheney (yes, that Lynn Cheney). He's of the foreign variety, definitely autocratic, and really hates homesteaders (though none of this is necessarily seen as a bad thing, and he's certainly not the antagonist).
- Charles Goodnight, a Real Life Cattle Baron, appears as a heroic character in several of J.T. Edson's novels. Goodnight also makes a brief but important appearance near the end of Larry McMurtry's Streets of Laredo
- Doña Bárbara is the Latin American (in fact, Venezuelan) take on this trope, and a female one, to boot. In fact, whenever wealthy people from "El Llano" (the Venezuelan flatlands) appear in Telenovelas they tend not only to represent this trope, but reference Doña Bárbara in a way or another.
- Another novela example is the Brazilian soap O Rei do Gado (literally, the King of the Cattle).
- A rare benign protagonist example would be Ben Cartwright from Bonanza.
- Pete Thornton appears as one in the two MacGyver (1985) dream episodes set in the Wild West: "Serenity" and "MacGyver's Women".
- Frontier Circus: One attempts to drive a peaceful religious settlement off their land in "The Good Fight". After he gets cold feet, his foreman murders him and uses his widow to keep the scheme going.
- Firefly, by virtue of being an Old-West-inspired Feudal Future, has literal cattle barons. One of them hires Mal to smuggle his livestock in "Shindig".
- "Class of '57" by The Statler Brothers: One of the classmates, John (in the final verse) is one of these ("John is big in cattle"...).
- The New California Republic having a fair number of these is actually a minor plot point in Fallout 2: in the plot-apocalyptic wastes of western America, food is one of the most important things to have. The NCR's economic strength is built on the back of its dominance of the brahmin market, so the brahmin barons are one of the more important groups in the NCR. The mostly sympathetic senator Roger Westin is one of them.
- Heck Gunderson of Fallout: New Vegas is a brahmin baron (brahmin being two-headed mutated cows of post-apocalyptic America). Unsurprisingly, he's also earned his power via cutthroat tactics and forcing other ranchers off their land at gunpoint. One sidequest deals with one of the ranchers whose land he stole who wants revenge.
- Their disproportionate power in the NCR is brought up again in New Vegas, as they're able to get away with trying to provoke a mostly peaceful village of super mutants to attack first because they suspect they've been killing their brahmin.
- In the Whateley Universe, superpowered mutant Fantastico comes from a family of Texas cattle barons.
- Quite a number of them popped up across the various colonies in 19th-Century Australia, often referred to as "squatters" (though the term has come to mean someone illegally living in a home without paying rent).