Ian Ernest Gilmore Evans (né Green; May 13, 1912 – March 20, 1988) was a Canadian–American jazz pianist, arranger, composer and bandleader. He is widely recognized as one of the greatest orchestrators in jazz, playing an important role in the development of cool jazz, modal jazz, free jazz, and jazz fusion. He is best known for his acclaimed collaborations with Miles Davis.

Gil Evans was born in Toronto, Canada on May 13, 1912 to Margaret Julia McConnachy. Little is known about Evans’ biological father, although a family friend said that he was a doctor who had died before Evans was born. Originally named Gilmore Ian Ernest Green, Evans took the last name of his step-father, John Evans, a miner. The family moved frequently, living in Saskatchewan, British Columbia, Washington, Idaho, Montana, and Oregon, migrating to wherever Evans’ father could find work. Eventually, the family ended up in California, first in Berkeley, where Evans attended the ninth and tenth grades, then in Stockton, where he attended Stockton High School, graduating in 1930. During this time, Evans’ father took a job with the Western Pacific Railroad, and Evans began living with friends, later renting a room in a boarding house. After graduating, Evans attended the College of the Pacific in Stockton but then transferred to Modesto Junior College.After a year in Modesto, Evans left and moved back to Stockton.