On May 9, 1964, the great Louis Armstrong, age 63, broke the Beatles’ stranglehold on the U.S. pop charts with the #1 hit “Hello Dolly.” Following the ascension of “I Want to Hold Your Hand” to #1 in early February, the Beatles held the top spot on the Billboard Hot 100 for three and a half solid months—longer than any popular artist before or since. Over the course of those months, the Fab Four earned three consecutive #1 singles (a record); held all five spots in the top five in early April (a record); and had a total of 14 songs in the Billboard Hot 100 in mid-April (yet another record). But just when it seemed that no homegrown act would ever stand up to the British invaders, one of the least likely American stars imaginable proved himself equal to the task: jazz trumpeter Louis Armstrong. In a way, it was entirely appropriate that a titan such as Louis Armstrong would be the artist to end the reign of the first foreign group ever to take over the American pop scene. It can be argued, after all, that Armstrong bears more responsibility for shaping the course of 20th-century American music than Elvis Presley and Frank Sinatra combined. Louis Armstrong became one of jazz music’s first individual superstars as a young trumpet player in the 1920s and 30s, but more than that, he revolutionized jazz itself by turning it into an individual improvisational art form. The recordings Armstrong made with his Hot Five and Hot Seven combos between 1925 and 1927 are widely credited with creating much of the foundation for the future of jazz and blues performance and, by extension, of rock and roll. Armstrong’s own statement that “if it hadn’t been for jazz, there wouldn’t be no rock and roll,” was effectively endorsed by the Rock and Roll Hall of Fame, which inducted Armstrong as an “early influencer” in 1990. Of course, it wasn’t Louis Armstrong the young revolutionary, but Louis Armstrong the late-career light entertainer who knocked the Beatles from the top of the pops. By the early 1960s, Armstrong’s most important and influential work was already behind him, yet his famous charisma and ebullient personality were still enough to lift a show tune like “Hello Dolly” to the #1 spot on the pop charts—and over the Beatles—on this day in 1964.