January 1, 1885: Born in Stamford, Connecticut.
First published song, "Lonesome", is recorded by the Haydn Quartet. That recording reaches #3 on the Billboard charts. Later that year, Byron G. Harlan records it and hits # 6 with his rendition.
Charter member of American Society of Composers, Publishers and Authors (ASCAP).
Forms publishing firm.
Travels to England where he settles into a collaboration with Horatio Nicholls. Over the next three years, the pair produces "Among My Souvenirs", "Mistakes" and Shepherd of the Hills".
Returns to the United States.
Elected as a director at ASCAP. He would hold the same position until 1941.
Coming out of retirement, Leslie is again appointed to the Board at ASCAP. This second reign would last until 1953.