The song is about Oswald Mosely, but when performing in America, Costello would change the lyrics so that it would be about Lee Harvey Oswald. He assumed Americans had never heard of Oswald Mosely.
An interesting interview with the singer was posted this week on his website. He talks about his current fascination with old songs and the differences between northern and southern Minnesota.
Filmmaker Michael Rubenstone says seeing Stone's performance in the documentary about Woodstock was the start of his fascination with the reclusive music icon.