On 21 July 1956, Johnny Cash's "I Walk the Line" reached No. 1 on Billboard's country juke box chart, marking the first of 14 chart-topping hits he would achieve over three decades. The milestone came just two weeks after his Grand Ole Opry debut on 7 July 1956, where he performed the song at Nashville's Ryman Auditorium and met June Carter, his future wife and duet partner.

The song was unusual in structure, featuring five verses and no chorus while moving through three different keys, which showcased Cash's distinctive vocal range, including his signature bass notes. Its origins traced back to his time in the US Air Force in Germany, where a mangled recording tape produced a droning sound that stayed with him for over a year; he later wrote the song in 20 minutes after Carl Perkins suggested the title, and recorded it in Memphis with producer Sam Phillips and backing band The Tennessee Two. "I Walk the Line" was inducted into the Grammy Hall of Fame in 1998 and recognised by the Recording Industry Association of America and the National Endowment for the Arts.