Denver described how he wrote "Sunshine on my Shoulders": "I wrote the song in Minnesota at the time I call 'late winter, early spring'. It was a dreary day, gray and slushy. The snow was melting and it was too cold to go outside and have fun, but God, you're ready for spring. You want to get outdoors again and you're waiting for that sun to shine, and you remember how sometimes just the sun itself can make you feel good. And in that very melancholy frame of mind I wrote 'Sunshine on my Shoulders'."
It was originally the B-side of one of his earlier songs, "I'd Rather Be a Cowboy". As the Vietnam War came to an end, the song took on a new significance and began to receive airplay on adult contemporary radio stations. It entered the Billboard Hot 100 at number 90 on January 26, 1974 and moved into the number one spot nine weeks later, remaining at #1 for one week. The song also topped the adult contemporary chart for two weeks in 1974.
A television movie titled Sunshine, shown on NBC in 1973, used the song as a theme. The movie starred Cliff DeYoung and Cristina Raines. It told the story of a young mother in love and dying. High ratings prompted a TV series (also Sunshine) which ran for three months during the summer of 1974. The short-lived series began where the movie left off with the young widowed father (DeYoung) raising his stepdaughter (Elizabeth Cheshire).
In the movie Super Troopers, the character Farva explains to the rookie Rabbit how John Denver won the country music award for best artist. He refers to Mr. Denver as, "Mr. Sunshine on my God Damn Shoulders" John Denver.