David Douglas Duncan, one of the foremost photojournalists of the 20th century, whose subjects ranged from the US Marines’ epic stand at the Chosin Reservoir during the Korean War to Pablo Picasso at work and play, died Thursday in the south of France, according to news reports. He was 102.

Mr. Duncan described himself in his 2003 memoir, “Photo Nomad,’’ as “a man with cameras mostly focused on faces, grand adventures, and violence, recording a kaleidoscopic journey through much of his century.’’ There was a hungriness to Mr. Duncan’s eye, a visual avidity that kept him photographically active for eight decades.

“It all seemed so natural,’’ he wrote in “Photo Nomad’’, “so easy — just see it, aim at it, shoot it!’’

Equally gifted at portraying brutality and beauty, he was the artistic peer of his photojournalist friends Robert Capa, Alfred Eisenstaedt, and Henri Cartier-Bresson. Mr. Duncan, a decade their junior, was in many ways the last of the breed: brash, larger-than-life adventurers who took their cameras to exotic locales to reveal new worlds to magazine readers in the era before television had domesticated the image. As the world grew smaller, so did what was expected of photojournalism.

Mr. Duncan exemplified the classic photojournalist’s combination of independence and ego. When he published an article in Life magazine that questioned the likelihood of French victory in Indochina, it so angered Henry R. Luce, the magazine’s owner, he tried to browbeat Mr. Duncan, who refused to back down. Luce complained that having “a hell of a nerve . . . appeared to be one of [Mr. Duncan’s] techniques.’’ Both exasperated and impressed, he cabled Life’s managing editor, “Duncan didn’t fire me.’’

The photographer Mr. Duncan most resembled was Capa, a fellow free spirit with a penchant for fast cars, faraway places, and courage under fire. Just as Capa’s pictures of the Spanish Civil War and World War II did so much to define the visual record of those ­conflicts, so did Mr. Duncan’s photographs become the signature images of the Korean War.

His formula for combat photography was simple: “Be close — Be fast — Be Lucky.’’ It was no mistake that Mr. Duncan, who earned a Purple Heart, two Distinguished Flying Crosses, and four Air Medals as a Marine during World War II, capitalized “Lucky.’’ Mr. Duncan’s most memorable war photographs abjure combat and carnage, instead focusing on spiritual duress as expressed in the faces of men in battle.

Perhaps no other photographer has so well demonstrated, as he put it in “Photo Nomad,’’ that “war is in the eyes.’’ The close-up shots he took of Marines in Korea — mud caked, unshaven, blankly staring — are among the most eloquent portraits in photographic history. There’s a timelessness to Mr. Duncan’s war photography, an archetypal quality.

He titled his first book “This is War!’’, and so generic a title suits the images. Their equipment aside, these warriors could as easily be serving under Caesar or Charlemagne as MacArthur or Westmoreland (Mr. Duncan also covered the Vietnam War). No less an authority than Edward Steichen called “This is War!’’ “the greatest book of war photographs ever published.’’

Mr. Duncan met Picasso in 1956. The two hit it off, and over the next few years he took some 10,000 photographs of the painter, nearly all of them unposed. They are an unrivaled visual archive of a great artist’s life and work. Mr. Duncan published several books of his Picasso photographs: “The Private World of Pablo Picasso’’ (1958), “Picasso’s Picassos’’ (1961), “Goodbye Picasso’’ (1974), “The Silent Studio’’ (1976), “Viva Picasso’’ (1981), “Picasso and Jacqueline’’ (1988), and “Pablo Picasso: A Portrait’’ (1996).

The son of Kenneth Stockwell Duncan, a businessman, and Florence (Watson) Duncan, Mr. Duncan was born in Kansas City, Mo., on Jan. 23, 1916.

His sister gave him a 39-cent camera on his 18th birthday. Mr. Duncan took it with him to the University of Arizona, where he went to study archeology. Hearing of a fire at a nearby hotel, he rushed over with his camera. “It was to become the most significant single move of my life,’’ he wrote in his 1966 book, “Yankee Nomad.’’ He took a picture of a man fleeing the scene, who turned out to be the gangster John Dillinger.

Mr. Duncan transferred to the University of Miami. A photograph he took of a fisherman casting his net won second prize in Kodak’s National Snapshot Contest in 1936. Two years later, he graduated and became a freelance photographer. He sold his first magazine story to National Geographic. His work began to appear regularly in his hometown paper, The Kansas City Star. The American Museum of Natural History hired him to photograph an expedition to South America.

During World War II, Mr. Duncan served as a combat photographer in the South Pacific. “No Marine was ever more out of uniform,’’ he wrote in “Photo Nomad.’’ He photographed guerrillas behind Japanese lines in the Solomon Islands, kamikaze attacks off Okinawa, and the surrender ceremonies on the USS Missouri.

Joining the staff of Life in 1946, Mr. Duncan undertook a variety of assignments in the Near East and North Africa: Iranian nomads, the birth of Israel, Turkish cavalry on the Soviet border. He met his first wife, Leila Khanki, in Egypt. They married in 1947 and divorced in 1962. That same year, Mr. Duncan married Sheila Macauley, who survives him.

Mr. Duncan was working on a photo essay on classical Japanese art when the Korean War broke out. He spent the first six months of the conflict covering it, most of the time with the Marine First Division.

When they were evacuated after encirclement by Chinese forces in 1950, Mr. Duncan was, he later recalled, “the last live American’’ to leave North Korea.

Mr. Duncan resumed his Japanese project, shooting it in color, something he’d begun using in the Middle East a few years earlier. Mr. Duncan never abandoned black-and-white photography, but color became increasingly prominent in his work.

Mr. Duncan left Life in 1956 and went freelance. In Moscow that year, he photographed Nikita Khrushchev eating a bowl of ice cream and asked if he could shoot the art treasures of the Kremlin. “Start tomorrow,’’ the Soviet leader said.

The photographs became a book, “The Kremlin’’ (1960). Other books by Mr. Duncan include “I Protest!’’, a selection of his Vietnam photographs (1968); “Self-Portrait: U.S.A.’’ on the 1968 presidential campaign; “War Without Heroes’’ (1971); “The World of Allah’’ (1982); “Sunflowers for Van Gogh’’ (1986); and “A Secret Garden’’ (1992).

Mark Feeney can be reached at mfeeney@globe.com.