After studying at Norwich University for a year, he entered the United States Military Academy in June 1906.

[7][8] After commissioning, Selleck served with the 1st Field Artillery at Fort Sill in Oklahoma and Schofield Barracks in Hawaii.

[6] During World War I, Selleck received a temporary promotion to major in February 1918 before being sent to France with the 5th Division.

Selleck received a temporary promotion to lieutenant colonel in September 1918 and served as chief of staff of the VII Corps Artillery until November 1918.

Selleck served as a field artillery instructor with the New York National Guard from July 1921 to August 1925.

After being captured, Selleck survived the Bataan Death March and then was held in prisoner-of-war camps until August 1945.

[4][13][14] Their son Clyde Andrew Selleck Jr. (23 December 1930 – 12 May 2016) was a 1952 West Point graduate who retired from the Army Corps of Engineers as a colonel.

He died at a nursing home in Silver Spring, Maryland and was interred next to his wife at Arlington National Cemetery on 11 January 1973.