Italian actress Monica Vitti and producer director Gualtiero Jacopetti attend a party for movie celebrities in a fashionable night club in Rome on July 6, 1968. (GIANNI FOGGIA/ASSOCIATED PRESS)

Gualtiero Jacopetti, 91, an Italian moviemaker who made an art form of documenting the bizarre, the ironic and the unclothed with the provocative film “Mondo Cane” and the “shockumentaries” it spawned, died of undisclosed causes Aug. 17 at his home in Rome, according to Italian media reports.

“Mondo Cane,” which Mr. Jacopetti directed with Paolo Cavara and Franco Prosperi, was a worldwide sensation when it was released in 1962, and it has maintained a devoted following.

Decades before YouTube became a repository for videos of toilet-trained cats and backyard stunts, Mr. Jacopetti traveled around the globe filming all that was weird. He compiled the material into a film that was called, in English, “a dog’s world.”

The result was something on the order of road kill.

“Those with frail stomachs,” wrote a Washington Post reviewer, “are well advised to stay away.”

Few people could resist.

Critics resorted to bulleted laundry lists to convey the expanse of Mr. Jacopetti’s 105-minute montage of raw human absurdity: Americans engaging in histrionics at a pet cemetery as a poodle urinates on a gravestone; French women force-feeding geese to make foie gras, quickly contrasted with scenes of island women bingeing on tapioca to make themselves more heftily attractive; a woman in New Guinea nursing a piglet, followed by images of the wanton slaughter preceding a feast of pork.

If the images in “Mondo Cane” were shocking, the film’s opening narration advised, it was “because there are many shocking things in this world.”

Adding to the film’s mischief was a lushly romantic and highly misplaced score by Nino Oliviero and Riz Ortolani, which featured the song “More.” The composition was nominated for an Oscar and helped immortalize a film that was about everything but “the greatest love the world has known.”

Because of the financial success of the original, Mr. Jacopetti and his team rushed out a sequel, “Mondo Cane 2.” Other filmmakers tried to capi­tal­ize on the craze. Russ Meyer came out with “Mondo Topless” in 1966. John Waters made “Mondo Trasho” in 1969. Similar offerings included “Mondo Bizarro,” “Mondo Freudo,” “Mondo Hollywood” and “Mondo Mod.”

The word “mondo” entered English usage in fittingly over-the-top fashion. The Italian noun became an English noun, adjective and adverb to mean, in most cases, “extremely” — when the word “extremely” isn’t enough.

In 1963, Mr. Jacopetti made “Women of the World,” essentially an all-female version of “Mondo Cane” that featured ample scenes of bare breasts.

Not everything in the film appealed to lower-order needs. Former U.S. treasurer Elizabeth Rudel Smith was presented as the consummate career woman. And Mr. Jacopetti was “genuinely perceptive,” wrote New York Times movie critic A.H. Weiler, in filming two nuns traveling by Jeep through the beautiful African landscape to minister to Masai natives. “It is a vignette that leaves a truly vivid and lasting effect,” Weiler said.

Controversy and criticism followed Mr. Jacopetti and his collaborators for their 1966 film “Africa Addio” (Farewell Africa), ostensibly a graphic look at the continent’s post-colonial struggle.

The filmmakers had collected three years’ worth of footage from Congo, Zanzibar, South Africa and other countries to depict episodes of human brutality and carnage, including mercenary killings and the massacre of wildlife.

Mr. Jacopetti was accused of fostering a racist view of blacks as savages — although the former colonizers were also portrayed in an unsavory light. The most damaging publicity that befell the film was the accusation that Mr. Jacopetti and his crew had encouraged an execution by mercenaries in Congo to benefit their movie. The filmmakers were compelled to clear their name in an Italian court.

“Africa Addio,” which Mr. Jacopetti regarded as his favorite effort, was a commercial failure. It fared better at the box office a few years later, when it had a second release in the United States under the name “Africa Blood and Guts.”

Partly in an effort to redeem their reputation, Mr. Jacopetti and Prosperi made “Goodbye Uncle Tom” (1971), an account of two filmmakers who travel back in time to portray the slave trade in America. It met with a thud, and Mr. Jacopetti soon returned to journalism.

Gualtiero Jacopetti was born Sept. 4, 1919, in Barga, Tuscany. During World War II, he collaborated with the Allied troops as they made their way up the spine of Italy.

According to Italian news reports, he will be buried in Rome next to his onetime girlfriend Belinda Lee, an English actress who died in a 1961 car wreck in California. Mr. Jacopetti was injured in the accident. He married and had a daughter, but a complete list of survivors was unavailable.

Mr. Jacopetti and his movies continued to be an object of curiosity, but “Mondo Cane” and its ilk began to look rather tame with the arrival of more explicit TV programming, particularly “reality” TV.

“After the advent of TV, everything is consumed in a different way,” he once said. “Today nothing is unknown anymore; with TV, everything is known.”