In the summer of 1914, while working as a soda jerk at the Poodle Dog Café, Ellington wrote his first composition, "Soda Fountain Rag" (also known as the "Poodle Dog Rag"). He created the piece by ear, as he had not yet learned to read and write music. "I would play the 'Soda Fountain Rag' as a one-step, two-step, waltz, tango, and fox trot", Ellington recalled. "Listeners never knew it was the same piece. I was established as having my own repertoire." In his autobiography, Music is my Mistress (1973), Ellington wrote that he missed more lessons than he attended, feeling at the time that piano was not his talent.
Ellington continued listening to, watching, and imitating ragtime pianists, not only in Washington, D.C., but in Philadelphia and Atlantic City, where he vacationed with his mother during the summer. He would sometimes hear strange music played by those who could not afford much sheet music, so for variations, they played the sheets upside down.