Lieutenant Colonel Earl Hancock "Pete" Ellis (December 19, 1880 – May 12, 1923) was a United States Marine Corps Intelligence Officer, and author of Operations Plan 712: Advanced Base Operations in Micronesia, which became the basis for the American campaign of amphibious assault that defeated the Japanese in World War II. Ellis' prophetic study helped establish his reputation as one of the forefront of naval theorists and strategist of the era in amphibious warfare, foreseeing the imminent attack from Japan leading to the island-hopping campaigns in Central Pacific. Earl Ellis became the Marine Corps' first spy whose mysterious death became enclosed in controversy.