"I Didn't Know About You" is a jazz standard with music by Duke Ellington and English lyrics by Bob Russell. It began as an Ellington instrumental, first recorded in 1942 under the title "Sentimental Lady", with Johnny Hodges on alto saxophone. That instrumental reached number one on the Harlem Hit Parade in 1943. A vocal version, with Joya Sherrill singing, was recorded in 1944. Woody Herman and His Orchestra recorded it on 5 April 1944, and the single was released in 1945. Count Basie and His Orchestra, with a vocal by Thelma Carpenter, reached No. 21 on the Billboard charts in 1945, and other recordings that year came from Ellington, Mildred Bailey, Jo Stafford and Lena Horne. Alec Wilder judged its main strain the most melodic, vocally, of the three Ellington-Russell songs. Later recordings include versions by Patti Page and June Christy (1956), Ella Fitzgerald and Abbey Lincoln (1957), Jo Stafford (1960), and Charlie Rouse with Thelonious Monk (1966).
