WASHINGTON — John Gavin, a Hollywood actor who had major roles in the Roman epic ‘‘Spartacus’’ and Alfred Hitchcock’s classic thriller ‘‘Psycho’’ before being named US ambassador to Mexico, where he had a tumultuous five-year tenure in the 1980s, died Feb. 9 at his home in Beverly Hills, Calif. He was 86.

A spokesman, Budd Burton Moss, announced the death but did not specify a cause.

After serving as a Navy officer in the 1950s, Mr. Gavin was hoping to work as a technical adviser on a movie about an aircraft carrier. The film’s producer, an old family friend, suggested that the strapping, 6-foot-4 Mr. Gavin have a screen test.

He found modest success as a contract actor at Universal studios, where he was sometimes hailed as ‘‘the next Rock Hudson.’’ Mr. Gavin had the lead role in ‘‘A Time to Love and a Time to Die’’ (1958), playing a German soldier returning to his ravaged homeland and falling in love during World War II. He received a Golden Globe Award as most promising new actor.

‘‘He is handsome,’’ Hollywood columnist Hedda Hopper wrote at the time, ‘‘and has a silken sort of threat which gives women little chills up and down the spine.’’

The film’s director, Douglas Sirk, next cast Gavin as Lana Turner’s suitor in the 1959 melodrama ‘‘Imitation of Life,’’ which explored issues of racial identity. In 1960, he played Julius Caesar in Stanley Kubrick’s Oscar-winning ‘‘Spartacus,’’ alongside Kirk Douglas, Tony Curtis, and Laurence Olivier.

The same year, Mr. Gavin appeared in Hitchcock’s ‘‘Psycho’’ as Sam Loomis, the lover of Janet Leigh’s character, Marion Crane. In a climactic scene in the film, he ends up at the Bates Motel with Marion’s sister, played by Vera Miles, and has a chilling encounter with Norman Bates, the murderous character portrayed by Anthony Perkins.

Mr. Gavin later said he was ‘‘terribly disturbed’’ by the violence and sexual innuendo of ‘‘Psycho.’’

In other film roles, Mr. Gavin appeared with such acclaimed actresses as Sophia Loren, Susan Hayward, and Doris Day, yet never broke through to mass stardom. His acting was often considered wooden, and Hitchcock called him ‘‘the stiff.’’ In a review of ‘‘A Breath of Scandal,’’ the film Mr. Gavin made with Loren, New York Post critic Archer Winsten wrote, ‘‘The actors act, and those who cannot, like Gavin, look beautiful.’’

Mr. Gavin was scheduled to play James Bond in ‘‘Diamonds Are Forever’’ (1971) before Sean Connery was lured back with a hefty salary to play the role he had given up four years earlier. In 1973, Mr. Gavin was again set to portray Bond before the producers decided to go with British actor Roger Moore in ‘‘Live and Let Die.’’

During his diminishing acting career, Mr. Gavin was active in other pursuits, including serving as president of the Screen Actors Guild from 1971 to 1973. He had widespread business interests throughout Latin America and spent several years as special adviser to the head of the Organization of American States.

In 1980, he campaigned for his old friend from Hollywood, Ronald Reagan, the Republican nominee for president. After Reagan won the election, he nominated Mr. Gavin as ambassador to Mexico.

Mexican authorities and some State Department officials were perplexed at the choice. At the time, the US Embassy in Mexico City, along with consular offices throughout the country, constituted the largest American diplomatic mission in the world.

Although he had been a Navy intelligence officer and was fluent in Spanish and Portuguese, Mr. Gavin had no previous diplomatic experience.

Mexicans knew him primarily for television commercials in which he advertised Bacardi rum. Wags joked that an equivalent appointment would be to name Mario Moreno, a popular comic actor known as Cantinflas, ambassador to the United States.

The Senate confirmed Mr. Gavin for the post in 1981. From the beginning, as the Los Angeles Times noted five years later, ‘‘he displayed an instinctive ability to antagonize just about everyone whom diplomats usually try to cultivate.’’

He was absent from Mexico a third of the time, often spending four-day weekends in Los Angeles. He insulted journalists from both Mexico and the United States, telling some that he knew their bosses and could get them fired.

His meetings with Mexican clergy members and opposition political groups were interpreted as efforts to interfere in the country’s internal politics. There were calls for him to be declared persona non grata and expelled from the country.

When Mr. Gavin resigned his ambassadorship in 1986, a column in Mexico City’s El Universal newspaper described him as ‘‘arrogant, imprudent, and meddlesome’’ and as ‘‘one of the most ghastly ambassadors’’ to Mexico in years.

A political cartoon posed the question, ‘‘Now, who will follow, Woody Allen or Jerry Lewis?’’

Nonetheless, Mr. Gavin had strong supporters in the United States, particularly among conservatives who praised his straight talk and unyielding nature.

‘‘Too often in the past we have dealt with Mexico from a condescending position where we look the other way at corruption and inefficiency and deal in vague diplomatic platitudes,’’ said Senator Phil Gramm, a Texas Republican. ‘‘He never forgot that he was in Mexico to represent the United States, not to represent Mexico to Washington.’’

Mr. Gavin was born April 8, 1931, in Los Angeles. His name at birth was Juan Vincent Apablasa. When his Mexican-born mother remarried, he took the last name of his stepfather, Golenor.

He graduated in 1952 from Stanford University, where he studied Latin American economic history, and served in Asia and Panama with the Navy from 1952 to 1955.

In his first film roles in 1956, he appeared as John Gilmore and John Golenor before changing his last name to Gavin.

His first marriage, to actress Cicely Evans, ended in divorce. He leaves his wife since 1974, actress Constance Towers of Beverly Hills; two daughters from his first marriage; and two stepchildren.

After he resigned as an ambassador, Mr. Gavin worked for the Atlantic Richfield oil company and later became president of the parent company of the Spanish-language television network Univision. He had other far-flung business interests and served on a variety of corporate boards. He never returned to acting.

During his Senate confirmation hearings in 1981, Mr. Gavin was asked how an actor with no diplomatic training could presume to become an ambassador.

He wryly noted that he could show the senators 40 movies ‘‘to prove that I’m no actor.’’