Nguyen Van Thieu briefly joined the Communist forces before abandoning them and serving in the French-controlled Vietnamese army.

He served as chief of state under Nguyen Cao Ky from 1965-67. In 1967, he ran successfully for President of South Vietnam and held that position until the fall of Saigon, South Vietnam's capital, became imminent in 1975.

Just prior to the Communist victory, Thieu emigrated to Taiwan before taking up residence in the United Kingdom.