He was born in Aurora, Illinois to Adalaide Rhoda (née Parker) and Eli Holbrook Gale, a physician.

In 1909, he was badly burned in an electrical accident at the Observatory and he required skin grafts during two months' hospitalization.

During World War I he served in the United States and France, obtaining the rank of lieutenant colonel.

He was cited by general John J. Pershing for "especially meritorious and conspicuous service" and he was awarded the Legion of Honor by the French authorities.

[2][4] In 1938, Gale's racism became a prominent issue after Otto Struve organised an astronomy course at the university to be taught by Yerkes Observatory staff, including future Nobel Prize-winner, the Indian Subrahmanyan Chandrasekhar.