Man power! Us looks back at music's most successful all-male groups, from One Direction to the Backstreet Boys
Adding to the U.S.'s Irish-British invasion, Max George, Siva Kaneswaran, Jay McGuiness, Tom Parker and Nathan Sykes hit the ground running a year prior to One Direction making it big. Their most popular hit in the U.S. "Glad You Came," peaked at No. 3 on the Billboard Hot 100.