On April 11, 1938 the Society for the Preservation and Encouragement of Barbershop Quartet Singing in America was founded in Tulsa, Oklahoma, marking the official celebration of Barbershop Quartet Day. The image of four wearing straw hats singing together with complex harmonies could be considered a cultural cornerstone of the 1940s. However, Barbershop Quartet is by no means an American invention; the popularity of barbershops in England amongst men during the time of Shakespeare extended as far as in-house entertainment, often taking the form of a lutist providing a melody to which the queuing patrons could harmonize with. This idea and practice became popular in America in the West during the late 1800s, though a banjo was often used instead of a lute. Can't remember the last time I saw one
