"That'll Be the Day" had its genesis in a trip to the movies by Holly, Allison and Sonny Curtis in June 1956. The John Wayne film The Searchers was playing. Wayne's frequently-used, world-weary catchphrase, "That'll be the day." inspired the young musicians. Soon after, Holly along with Allison wrote a song centered on that phrase. They first recorded it on July 22, 1956, at the Decca Records studio in Nashville, Tennessee.
~Source Wikipedia

On February 3, 1959, on what has become known as "The Day the Music Died", Buddy Holly died in a small-plane crash in Iowa, a tragedy that also claimed the lives of fellow musicians Ritchie Valens and J. P. "The Big Bopper" Richardson, as well as pilot Roger Peterson.