The American chess player—and second-ranked player in the world—Fabiano Caruana (right) in a match against the Russian player Sergey Karjakin at the Candidates Cup, last month. PHOTOGRAPH BY SERGEI ILNITSKY / EPA

Last month, in Moscow, Fabiano Caruana played chess for two weeks at the Candidates Cup, whose winner, each year, goes on to face the sitting world champion. By the end, the twenty-three-year-old American—born in Miami, raised in Brooklyn, with no formal education after middle school other than chess-studying stints in Madrid, Budapest, Lugano, and elsewhere—was one game away from earning the right to challenge Magnus Carlsen, the twenty-five-year-old Norwegian who has been the best chess player in the world for much of the past six years, and who, in 2014, achieved the highest chess rating in history.

“Had Fabiano won that game,” Yasser Seirawan, a four-time U.S. champion, former world top ten, and chess commentator, told me recently, with characteristic ebullience, “chess in America would have gone under a renaissance almost overnight, because we’ve got skin in the game. He would have played a match in November, in the Big Apple, against Carlsen, for the world championship. Chess in coffee shops and parks would have swollen.” Caruana lost the deciding match to the twenty-six-year-old Russian player Sergey Karjakin, who is ranked eighth in the world, six spots below Caruana. “Americans gravitate towards champions—full stop, end of story. You don’t need Bobby Fischer,” Seirawan said, referring to the greatest American chess player of all time, whose heyday was the nineteen-sixties and seventies. “You just need a champion.”

“It would have been a big deal,” Caruana, a sparrow-like, bespectacled young man, quietly confessed over coffee this week, after winning the U.S. Chess Championship, in St. Louis. “The last time an American was playing for a world championship was in 1972: Fischer against Spassky. The rivalry isn’t the same now: there isn’t the clash of nations or Cold War. But it would still be a big deal. Because I would have had a chance to become world champion and it would also have been the youngest world-championship match in history. It would have been cool.”

Fifty thousand dollars richer from last week’s win, but not much more famous, Caruana considered this alternate universe, which may still come to pass a few years hence. Caruana recently bought a house in St. Louis. “I like to invest in real estate,” he said. (He also owns homes in Florida.) “I’m not really looking for flashy cars.” But the location was key: while New York, and Manhattan, in particular, has long been America’s foremost incubator of chess players, it has been eclipsed in the past few years by the Midwestern city best known for its professional baseball team, its tornadoes, and its barbecue. “Nobody had any idea St. Louis could become a chess hub,” Caruana told me. Seirawan, who retired as an active tournament grand master in 2003, agreed. “If you had said back then, ‘Since your retirement, the center of chess has moved to the Midwest,’ I’d go, ‘Really? Chicago?’ ”

The unlikely shift can be attributed almost entirely to the efforts of a deep-pocketed retired financial executive named Rex Sinquefield, best known, previously, for helping create the first S. & P. index funds, in 1973, and for leading what Bloomberg Businessweek has called “a crusade against the income tax.” Raised in a St. Louis orphanage, Sinquefield didn’t learn to play chess until the ancient age of thirteen, when his uncle Fred taught him. “The second time we played,” he told me, “I beat him. I always felt a little guilty.” He went on to play in high school and college, still in St. Louis. These days, he plays some twenty online games at a given time, he says, describing himself as a “decent club player” with “a healthy addiction.” After moving back to Missouri, more than a decade ago, he decided to start a chess club. He believes that the game represents “everything valued by Western civilization, and maybe Eastern civilization: intelligence, judgment, study, hard work, intuition, calmness under pressure—all of that is on the line with chess.”

The amount of money that Sinquefield has since invested in Missouri chess is difficult to calculate, but estimates are well into the tens of millions. Sinquefield describes it simply as “a lot.” “The family joke,” his wife, Jeanne Sinquefield, told me, “was I let Rex do chess because ‘How expensive could it be?’ ” She, incidentally, has since helped persuade the Boy Scouts of America to create a chess merit badge, which more than a hundred thousand scouts have earned.

Thanks to Sinquefield’s efforts, there is now a “chess campus” in St. Louis, near Forest Park.* There, a visitor will find the largest chess piece in the world (a fourteen-foot-and-seven-inch-tall queen), sitting outside the World Chess Hall of Fame, which moved to St. Louis in 2011, three years after the opening of the six-thousand-square-foot Chess Club and Scholastic Center of St. Louis, which has more members than New York’s famed Marshall Chess Club. (The St. Louis club works with more than a hundred Missouri schools, mostly in the St. Louis area.) For eight years running, the U.S. Chess Championship has been held at the club, as has the Sinquefield Cup, an international tournament whose online broadcast had 1.5 million viewers last year. Congress declared St. Louis the nation’s “chess capital” in 2013. Even the St. Louis Cardinals had a chessboard installed in their locker room, just last week: the team’s manager, Mike Matheny, loves the game, and his players are learning.

“Imagine that this city would become the most noticeable spot, chess spot, on the world map,” Garry Kasparov, arguably the greatest chess player ever, alongside Fischer, told the crowd gathered at the U.S. Championship award ceremony. Kasparov declared that “now, here in St. Louis, we are facing the renaissance of the great game of chess.” Maurice Ashley, a chess grand master and the first black player inducted into the Hall of Fame, is similarly bullish about chess in America. Ashley lives in Brooklyn and founded the Harlem Chess Center. “Right now,” he told me, “there are a few countries with head starts: China, Russia, India. But the U.S. now has collected a core talent base—three of the top ten players in the world—and with the scholastic programs we have and the initiatives happening around the country, led by the one here in St. Louis, the United States is fast becoming the best chess country on Earth. Which is a wild thought, given that Bobby Fischer was this one lone ranger in 1972. Now we have talent up the wazoo.”

A true renaissance arguably also requires broader public interest in—and comprehension of—the game, which remains mysterious to many potential fans. Hoping to put its American stars in a more familiar context, the director of the chess club in St. Louis, Tony Rich, compared Caruana to golf’s Jack Nicklaus: “Kind of that veteran who doesn’t go on the emotional roller coaster—if he’s winning or losing at the board, he has a similar posture, has a good poker face.” Caruana’s American rival, Hikaru Nakamura, Rich continued, “is John McEnroe. He’s brash, he’s ego, he knows he’s going to win and will tell you his opinion. I remember when Ray Robson”—currently the fifth-ranked American chess player, who is all of twenty-one—“was still very young and playing in the junior championship, one of the commentators asked Nakamura, ‘What are your thoughts on Ray?’ And Hikaru said, ‘Eh. Not much natural talent, he just works really hard.’ ”