Art is booming in London. But the giddy Cool Britannia cultural mindset that swung London in the mid-1990s has been replaced: American art is at the forefront of London’s buoyant art scene. This season, exhibitions showcasing American painters and photographers will be a mainstay of leading London artistic institutions.

Pop art in particular is in vogue this fall. The National Portrait Gallery’s exhibit “Pop Art Portraits,” which runs between October 11 and January 20, brings together work by British and American artists from the 1950s and ’60s. Esteemed English painters feature in the exhibition, including David Hockney, Richard Hamilton, and Peter Blake, but it’s the Americans — Andy Warhol’s self-portraits and Marilyn Monroe screenprint series, Roy Lichtenstein’s iconic “In the Car,” and Ray Johnson’s portraits of Elvis Presley and James Dean — that really drive the show. Monroe herself gets a room all to herself in the NPG exhibit.

Twentieth-century American icons also show up in the exhibition “The Painting of Modern Life,” at the South Bank Centre’s Hayward Gallery. Opening on October 4, the show explores how photographic imagery has influenced paintings. Among the 100 pictures are works from Andy Warhol’s 1960s “Death and Disaster” series, including “Race Riot” (1963) and “Big Electric Chair” (1967), and Gerhard Richter’s “Woman With Umbrella” (1964) depicting Jackie Kennedy grieving her husband’s assassination. The Hayward Gallery has also shown its American leanings in the past by devoting shows to Lichtenstein and minimalist fluorescent light artist Dan Flavin.

Other American highlights in London include the Serpentine Gallery’s exhibition of the work of filmmaker and contemporary artist Matthew Barney, until November 11. There will also be a retrospective of Lee Miller at the Victoria and Albert Museum. Running through January 6, the show commemorates the 100th anniversary of Miller’s birth in Poughkeepsie, N.Y. And in October, the Piccadilly’s Royal Academy, to which the American philanthropist Paul Mellon left $5 million in his will, presents an exhibition of his outstanding artistic legacy. Mellon’s is the largest British collection outside the UK, presently exhibiting at the Yale Center for British Art in New Haven.

The director of the Hayward Gallery, Ralph Rugoff, who hails from New York, ascribes the sheer volume of American exhibitions to London’s increasingly globalized nature. “The art scene is much more international in outlook than it was,” he said. “This is a reflection of the fact that the demographic in London has become more international and the city’s position as a world financial center.”

And it’s not just modern art that is the big draw. The most successful American-themed exhibition this year was “A New World: England’s first view of America,” which ran last spring at the British Museum. For the first time in 40 years on British soil, the Museum displayed English artist’s John White’s watercolor drawings of North Carolina Algonquian Indians made while on pioneering British expeditions to Virginia in the 1580s. The only surviving visual record of this period of America’s history, the exhibition proudly recorded the response of eight present-day North Indian chiefs. “A New World” travels to New Haven’s Yale Center for British Art next March.

The secretary and chief executive of the Royal Academy, Charles Saumarez Smith, said he has taken note of the interest in American art in London. “Over recent years, there have been a large number of U.S.-related exhibitions demonstrating the appetite for, and public interest in, American culture,” Mr. Saumarez Smith, said. Mr. Saumarez Smith previously worked as the director at the National Portrait Gallery, where he oversaw the sweepingly historical “Americans” exhibition, and at the National Gallery, which last year displayed the work of John Singer Sargent and James McNeill Whistler, among others, in “Americans in Paris 1860-1900.” “Until recently people were unfamiliar with American art, so it has been a process of discovery,” Mr. Saumarez Smith said.

Such interest has expanded beyond traditional American painting. A curator at the Victoria and Albert Museum in South Kensington, Sonnet Stanfill, spent two-and-a-half years evaluating up-and-coming designers in New York before selecting outfits by 20 designers, including Zac Posen and Thom Browne, to show at “New York Fashion Now,” which is on display at the museum until the middle of this month. Ms. Stanfill, herself an American, said the exhibit probably wouldn’t have happened a decade ago. “The V&A has in the past not emphasized North American fashion because of its geography and where its designs are located; London and Paris have tended to be the areas where the collection is focused. But this exhibition allowed us to engage our public with what is going on in contemporary American fashion rather than doing a retrospective.”

By far, the most popular American artist in London is Andy Warhol. In addition to his featured pictures at the Hayward and the NPG, shows, Warhol currently has a major retrospective in Edinburgh, a West End show lining up his work alongside that of guerrilla artist Banksy, and an exhibition in which his last self-portraits have been re-appropriated by British modern artist Gavin Turk. In addition, his cinematic output is presently the subject of a comprehensive two-month film festival at London’s flagship repertory cinema BFI Southbank. Had he still been in the land of the living and in London right now, even such an inveterate self-publicist as Warhol might have considered himself a tad overexposed.