
"I Thought About You" is a 1939 popular song composed by Jimmy Van Heusen with lyrics by Johnny Mercer. It was one of three collaborations Van Heusen and Mercer wrote for the then recently established Mercer-Morris publishing company. The lyrics were inspired by Mercer's train trip to Chicago. Mercer has said about the song: "I can remember the afternoon that we wrote it. He (Van Heusen) played me the melody. I didn't have any idea, but I had to go to Chicago that night. I think I was on the Benny Goodman program. And I got to thinking about it on the train. I was awake, I couldn't sleep. The tune was running through my mind, and that's when I wrote the song. On the train, really going to Chicago." Martin's arrangement is played in the key of C.