Henry Kimball Hadley (20 December 1871 – 6 September 1937) was an American composer and conductor.Hadley was born in Somerville, Massachusetts, to a musical family. His father, from whom he received his first musical instruction in violin and piano, was a secondary school music teacher, his mother was active in church music, and his brother Arthur went on to a successful career as a professional cellist. In the Hadley home, the two brothers played string quartets with their father on viola and the composer Henry F. Gilbert on second violin.Hadley also studied harmony with his father and with Stephen Emery, and, from the age of fourteen, he studied composition with the prominent American composer George Whitefield Chadwick. Under Chadwick's tutelage, Hadley composed many works, including songs, chamber music, a musical, and an orchestral overture.