The Louvin Brothers were an American country music duo composed of brothers Ira Lonnie Loudermilk (1924–1965) and Charlie Elzer Loudermilk (1927–2011), better known as Ira and Charlie Louvin. They helped popularize close harmony, a genre of country music. The brothers are cousins to John D. Loudermilk, a Nashville Songwriters Hall of Fame member.