Warren Mercer Oates (July 5, 1928 – April 3, 1982) was an American actor best known for his performances in several films directed by Sam Peckinpah, including The Wild Bunch (1969) and Bring Me the Head of Alfredo Garcia (1974).

According to the federal census of 1940, he was the younger of two sons born to Sarah Alice (née Mercer) and Bayless Earle Oates, who owned a general store.

After high school, he enlisted in the United States Marine Corps for two years (1946–1948), serving in its air wing as an aircraft mechanic and reaching the rank of corporal.

[5] Oates moved to Los Angeles, where in the 1950s, he began to establish himself in guest roles in weekly television Westerns, including Wagon Train, Tombstone Territory, Buckskin, Rawhide, Trackdown, Tate, The Rebel, Wanted Dead or Alive, The Virginian, Have Gun – Will Travel, Lawman, The Big Valley, Bat Masterson, and Gunsmoke.

In the episode "Subterranean City" (October 14, 1958) of the syndicated Rescue 8, Oates played a gang member, Pete, who is the nephew of series character Skip Johnson (Lang Jeffries).

In the story line, rescuers Johnson and Wes Cameron (Jim Davis) search for a lost girl in the sewer tunnels and encounter three criminals hiding out underground.

Oates also played in a number of guest roles on The Twilight Zone (in "The Purple Testament" and "The 7th Is Made Up of Phantoms" S5 E10 1963, in which he costarred with Randy Boone and Ron Foster), The Outer Limits ("The Mutant" [1964]), Combat!

While making a guest appearance on a segment of the Western television series Dundee and the Culhane, Oates managed to steal the show with his off-camera antics and bloopers that had everyone on the set rolling.

According to his wife at the time, Teddy, Oates had the choice of starring in Support Your Local Sheriff!, to be filmed in Los Angeles, or The Wild Bunch in Mexico.

In Bring Me the Head of Alfredo Garcia, the dark 1974 action/tragedy also filmed in Mexico, Oates played the lead role of Bennie, a hard-drinking, down-on-his-luck musician and bartender hoping to make a final score.

"[10] In addition to Peckinpah and Hellman, Oates worked with several major directors of his era, including Leslie Stevens in the 1960 film Private Property, his first starring role; Norman Jewison in In the Heat of the Night (1967); Joseph L. Mankiewicz in There Was a Crooked Man... (1970); John Milius in Dillinger (1973); Terrence Malick in Badlands (1973); Philip Kaufman in The White Dawn (1974); William Friedkin in The Brink's Job (1978); and Steven Spielberg in 1941 (1979).

He also starred in The Rise and Fall of Legs Diamond (1960), Return of the Seven (1966), The Split (1968), The Thief Who Came to Dinner (1973), Drum (1976), and played the title role in a 1971 crime drama, Chandler.

A political thriller with action film elements, Sleeping Dogs follows the lead character "Smith" (Neill) as New Zealand plunges into a police state, as a fascist government institutes martial law after industrial disputes flare into violence.

[11] On April 3, 1982, at the age of 53, he died of a heart attack while taking an afternoon nap at his home in Los Angeles, after having experienced chest pains and shortness of breath earlier that day.