* Chris Adams: The horse ridden by Yul Brynner is a Morgan, a versatile American breed known for its intelligence and stamina.
* Vin: Steve McQueen rides a Quarter Horse, a breed known for its speed and agility, particularly over short distances.
* Harry Luck: Robert Vaughn's character rides a Paint Horse, a breed recognized by its distinctive spotted coat.
* Lee: James Coburn's character rides a Thoroughbred, a breed known for its speed and racing capabilities.
* Britt: Eli Wallach's character rides a Mustang, a feral horse that had been roaming free in the American West.
* Chico: Horst Buchholz rides a Mexican Criollo, a breed known for its hardiness and adaptability.
* Calvera: The antagonist, played by Eli Wallach, rides a Spanish Mustang, which is a type of Mustang with a Spanish bloodline.
It's important to note that while the film features a variety of breeds, these are not exact matches. The filmmakers likely used a mixture of breeds, and the specific horse breeds of the actors may not have been explicitly identified in the film.