Col. Donald S. Marshall, 85, a 30-year Army veteran who saw action in World War II and Vietnam and an anthropologist who studied the languages and cultures of Polynesia, died of kidney failure Aug. 28 at his home in Alexandria.

Col. Marshall was born in Danvers, Mass., and was working on building a photography business in Boston before the outbreak of World War II. He enlisted in the Army in 1942 and was based in Panama, where he developed an interest in the San Blas Cuna Indians and a lifelong passion for anthropology and the study of complex systems.

He graduated magna cum laude in anthropology in 1950 and received a doctorate in 1956, both from Harvard University. In 1952, he studied in New Zealand as a Fulbright Scholar and made the first of more than 15 trips to Polynesia.

He studied the people of Mangaia, the southernmost of the Cook Islands, 650 miles southwest of Tahiti. He lived on Mangaia for more than a year after first studying Mangaian immigrants and their language in New Zealand. In addition to articles on general anthropology, material culture, social structure and linguistics, he was the author of the book "Ra'ivavae" (1961) and co-editor of the book "Human Sexual Behavior" (1971).

He returned to active duty with the Army in 1962 and served in Vietnam under Gen. Creighton W. Abrams Jr. as chief of the long-range planning element. He served two tours of duty in Vietnam, working on analyses of U.S. involvement in the war and strategies for the future.

He also served as deputy director of the SALT task force at the Pentagon and as director of strategy and assessment for the Defense Nuclear Agency. He retired in 1976.

His decorations included the Legion of Merit with oak-leaf cluster, the Bronze Star, the Joint Service Commendation with oak-leaf cluster and V device and the Army Commendation Medal.

After his retirement, he continued working on war and civil defense issues and was a founding member and executive director of the Military Conflict Institute. From 1980 to 1990, he worked at the University of California at Berkeley on the Vietnam Project, a collection of materials now housed at Texas Tech University.

In 1990, he became director of publications and research for Oceania at the Peabody Essex Museum in Salem, Mass., and editor of the Neptune. Ill health forced him to resign a second time in 2000, when he returned to Alexandria. Recently, he had finished editing a book on hieroglyphics.

His marriages to Shirley Marshall and Judith Marshall ended in divorce.

Survivors include four children from his first marriage, Mira Nan Marshall of Washington, Lance Martin Marshall of Columbia, S.C., Shirley Moana Marshall of Alexandria and Annabel Jean Baer of Alexandria; a daughter from his second marriage, Ariela Lucy Marshall of Cambridge, Mass.; a daughter from another relationship, Mildred "Mimi" Hereroa Richmond Le Menn of Papeete, Tahiti; and six grandchildren.