Eugene Sierras was born in Tucson, Arizona. He attended local schools and graduated from the University of Arizona. After graduation, he was called to active duty with the United States Navy. He received his commission as Ensign, USNR, and served on various ships and aircraft squadrons. He spent a total of eight years in fighter squadrons before being posted to several shore commands and staffs.
After retiring from the Navy, he returned to Tucson and completed a career with the Arizona Department of Public Safety as a civilian employee assigned to dispatching and licensing duties.