"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 Mercer-Morris publishing company started by Mercer and former Warner Bros. publisher Buddy Morris.
[1] The other two were called "Blue Rain" and "Make with the Kisses".
The lyrics were inspired by Mercer's train trip to Chicago.
"[1] Mercer wrote other songs about trains, including "Blues in the Night" (1940) and "On the Atchison, Topeka and the Santa Fe" (1946).