The 94-year-old British-Ghanaian photographer James Barnor calls himself “Lucky Jim” — he’s been “at the right place at the right time and met the right people” during a career spanning more than six decades and two continents, he said in a recent telephone interview from his London home.

It’s easy to believe him looking at “James Barnor: Accra/London,” a major retrospective of his work across genres — studio and street photography, photojournalism and fashion, images that range from the quietly intimate to the historical and iconic. Shown at the Serpentine Galleries in London in 2021, the exhibition is on view in an expanded form at the Detroit Institute of Arts, through Oct. 15.

Take a modest picture by Barnor from 1952 of Roy Ankrah, a Commonwealth featherweight boxing champion. Barnor decided to tag along when Ankrah and his wife, Rebecca, visited a friend — none other than the independence leader Kwame Nkrumah, who would go on to transform the Gold Coast from a British colony into the Republic of Ghana, becoming its first prime minister in 1957 and later its president. Barnor posed the three on Nkrumah’s couch — and then jumped into the frame, perching on an armrest, becoming part of a momentous history unfolding.

“This photo is quite revealing of James’s opportunism, his ability to make use of a scenario as it presents itself to him in the moment,” said Lizzie Carey-Thomas, who co-curated the Serpentine show. “He always seemed to be aware that something really important was happening.”

The exhibition’s more than 170 pictures chronicle Barnor’s crucial role representing an emerging nation and its people’s sense of self. He became Ghana’s first photojournalist in the 1950s, according to historians. He worked in London in the swinging ’60s, capturing the fashion and lives of Ghanaian expats and celebrities. In 1969, he returned to Accra to set up what is considered the country’s first color photography lab. (He returned to London permanently in 1994.)

While not yet as well known as some of his contemporaries — the American photojournalist and activist Kwame Brathwaite, say, or the Malian photographer Malick Sidibé — Barnor has been hailed in recent years. At a virtual celebration of Barnor in 2021, the photographers Tyler Mitchell and Samuel Fosso, and the artist Tourmaline were among those citing Barnor’s pioneering work and profound influence.

Antwaun Sargent, whose exhibition on young Black photographers, “The New Black Vanguard,” traveled to the D.I.A. in 2021-2022, said the Barnor retrospective is an important follow-up.

“The audience in Detroit got to see the here and the now — a younger generation of photographers like Campbell Addy, Awol Erizku, Tyler Mitchell, Ruth Ossai — and now they get to see who those photographers were looking back to,” Sargent said in an interview. “That’s not usually what happens — lots of institutions like to think that Black artists don’t have a history. This creates a lineage, and James is firmly in that lineage.”

Sargent added that “Barnor was the first to capture from inside the community our beauty and our notions of self-determination, and subsequent generations have had his photography to build on.”

Born in 1929, Barnor left school early and apprenticed in photography with a cousin, J.P. Dodoo, before establishing his first studio in Jamestown, Accra, in 1952. He called the space Ever Young, after a Norse myth about a goddess whose grove of apples conferred eternal youth — and indeed he captured the energies and aspirations of young Ghanaians in the years leading up to independence. Ever Young became a cultural center, and Barnor photographed everyone who gathered there: individuals and families, in both western-style and traditional dress; a female graduate of the police academy, hand raised in a crisp salute; a practitioner of yoga twisted into a series of asanas.

“A James Barnor photograph is instantly recognizable,” said Carey-Thomas. “It’s got a very particular quality of engagement with his subject. You’re really aware of the fact that he’s having a conversation with those sitters.”

He sometimes arranged his portrait subjects in the open air (“Daylight was free,” he laughed). He swapped his unwieldy studio equipment for a smaller camera to capture life on the city streets: young men piled into a roofless car out for a joyride; a man whose shirt reads “The Nigerian Superman” on a precariously balanced bicycle. Images of Ankrah and his family eating breakfast — a Kellogg’s Corn Flakes box displayed prominently on the table — or listening to records on a shiny new hi-fi hold up a mirror to a growing middle class, as hungry for the products and pleasures as their counterparts in the so-called developed world.

His career developed with the expansion of print journalism in West Africa. When The Daily Graphic, a newspaper owned by The Daily Mirror in London, set up operations in Ghana in 1950, it searched out local photojournalists. “The Mirror photographer looked at my work and said, ‘Oh, not quite, but we will train you.’”

The images Barnor created for Drum, a highly influential South African magazine with an international audience, along with The Daily Graphic and the U.K.-based Black Star picture agency during these years offer a rare insight into the first nation in Africa to decolonize. His photos at the D.I.A. show the rise of Nkrumah and his Convention People’s Party as well as the opposition National Liberation Movement, and British riot police breaking up political gatherings.

Nii Quarcoopome, a specialist in African art, who along with Nancy Barr, in the photography department, curated the D.I.A. show, said that Barnor’s political neutrality allowed him to move between factions. “He insisted that he was nonaligned. Nobody saw him as dangerous,” Quarcoopome said.

Pictures of the 1957 Independence celebrations in Accra include photos of then-Vice President Richard Nixon during his only visit to Africa, which many Ghanaians assumed was motivated by a desire to gain an economic foothold in the resource-rich region.

Two years after decolonization, Barnor boarded a ship for England on the advice of a friend — “London is the place for you,” the letter said. He did fashion and editorial photography for magazines aimed at West Indian, African and South Asian immigrants, and he pursued a university degree. He eventually got a job at a leading color processing lab.

Examples of his fashion photography are also on view in New York at the Brooklyn Museum’s exhibition “Africa Fashion.” Barnor recruited his African-origin models on the street and asked them to bring their own clothes to shoots —there was no budget for wardrobe.

One woman who posed, Erlin Ibreck, wrote in the retrospective’s exhibition catalog that she never thought of herself as beautiful when compared to the images she saw in other magazines, but working with Barnor “gave me the feeling that we were conspiring together to shatter accepted images of beauty, and to replace them with new and just as valid representations.”

In our conversation, Barnor expressed some regret about his decision to return to Ghana in 1969. “I was at the height of my fame and prosperity,” he said of London. “But I had the chance to take back to Africa something that wasn’t there — color photography, color printing, which in the 1960s was even new in Europe.”

Barnor pointed out a 1971 photograph of a shop assistant outside the newly established Sick-Hagemeyer color-processing laboratory in Accra. She holds brightly colored plastic bottles, with more arrayed at her feet — a carefully composed study in turquoise, coral and white. “This was my announcement,” Barnor explained. “I will take a color picture here in Ghana, develop it here and print it here, so you can see that I can do it.”

A few years later in Accra, Barnor opened a new business, Studio X23. But when the Ghanaian economy collapsed in the mid-1980s, he returned to London. Having lost his momentum as a photographer there, Barnor took a steady job as a cleaner at Heathrow Airport — a change in course that he has described as a typical immigrant story.

Quarcoopome, who grew up in Accra, learned of Barnor’s work from one of his elder brothers researching their family lineage. Intrigued, he and Barr traveled to Paris, where Barnor’s archive of 32,000 images is stewarded by the Galerie Clémentine de la Féronnière. Barr has been actively expanding the D.I.A.’s collection of African photography, including acquisitions of Barnor’s work, so bringing the Serpentine survey over made sense.

The curators were struck by the fact that Barnor “had so many stories — it was unusual to hear the voice of a living photographer who has such a great mind and retentive memory,” Quarcoopome said.

What he was not expecting was that the photographer’s stories would touch on his own history: “With every conversation comes a new revelation about my family,” Quarcoopome said.

The curator walked me over to a photo in the gallery showing an elegantly dressed woman in a caftan, leaning on a TV console topped by a silver tinsel Christmas tree. This was his uncle’s wife; on the wall behind her was a framed photograph — also by Barnor — of his uncle. So far, Barnor has discovered more than 75 photographs of Quarcoopome’s relations in his archive.

“It makes you feel like, ‘Oh my goodness, the only thing that James doesn’t know about me is my DNA,’” Quarcoopome said.

But the influence that his own family had on Barnor’s career was even more surprising. “My uncle was actually the one who gave him 10 British pounds to buy his first camera,” the curator said. “Barnor’s Studio X23 was in my grandfather’s backyard!”

Barnor, who wasn’t able to travel to Detroit for the exhibition, laughed when I recounted Quarcoopome’s words. “I’m the last one standing,” he said. “All the people I know now are younger than me. I have more stories to tell them than they themselves know.”