The Undefeated

After the American Civil War, Union Colonel John Henry Thomas (John Wayne) and company attacking Confederate soldiers led by Colonel James Langdon (Rock Hudson) are thrown together. After a crushing defeat, Langdon torches his plantation rather than have it fall into the hands of carpetbaggers. A group of Southerners accept the invitation of Emperor Maximilian to join them, and Langdon heads off with a wagon train of settlers to a new land. Thomas with his adopted Indian son Blue Boy (Roman Gabriel) bring a herd of 3,000 horses across the Rio Grande for sale in Durango, Mexico.Halfway there, Blue Boy notices that the tracks of a group of bandits indicate that they are planning an ambush for another group of travelers. Blue Boy and Thomas go to warn the travelers, who turn out to be the Confederates. Together the Americans repel a group of Mexican bandits who attack the Confederate wagon train.The two factions meet at a Fourth of July party and relive the war through a drunken brawl. They then split and go their separate ways. Meanwhile, Langdon's daughter has fallen in love with Blue Boy.When Langdon's company reaches Mexican Republican General Rojas (Antonio Aguilar), he holds the Southerners hostage for horses. Langdon is sent to get Thomas's horses as ransom. Thomas orders the herd to stampede into the General's camp as ransom payment for their former enemies.