This song has two inspirations: the Vulcan, which is the largest cast iron statue in the world, and the demotion of Pluto to a minor planet. John Prine explained to The Sun
: "I've always been kind of fascinated by the Vulcan in Birmingham, Alabama, and have tried to write a song about it for years. When I heard about how Pluto was demoted from a planet to a star (sic) I knew I wanted to write about it. I think the two stories compliment each other."
The Vulcan is the largest cast iron statue in the world, reflecting the iron and steel industry. Vulcan, the Roman god of fire and smithery, was a popular namesake for iron foundries during the Industrial Revolution.Pluto
was originally considered to be the ninth planet from the Sun, but the International Astronomical Union came up with a new definition for planets in 2006 that excluded Pluto after many other similar icy objects were found, including Chiron and Eris.