General McCaffrey was born in Omaha,Nebraska, and was a 1939 graduate of the U.S. Military Academy at West Point. During World War II, he was a Colonel and Chief of Staff with the 92nd Infantry Division and received the Silver Star for leading a nighttime reconnaissance mission in Italy.
 
In the Korean War, he commanded the 31st Infantry Regiment and fought at the Battle of the Chosin Reservoir. He received two additional awards of the Silver Star for his service in Korea.

In the 1960s, when hewas a senior officer in Europe and at the Joint Chiefs of Staff, General McCaffrey played a role in strengthening NATO defenses in the Cold War. From 1970 to 1972, he was deputy commander of U.S. forces in Vietnam as military operations were winding down. He retired in 1973.

After his military career, General McCaffrey was director of regional affairs for the Association of the United States Army and was a member of the senior review panel of the Central Intelligence Agency, working in coordination with the offices of three successive CIA directors.

He lived in Alexandria for many years and was a member St. Mary Catholic Church in Alexandria. He later attended the Cathedral of St. Thomas More in Arlington.

He was also a member of the Chosin Few, a Korean War veterans group.

Survivors include his wife of 66 years, Mary V. McCaffrey of Arlington; two children, retired Army General Barry McCaffrey of Alexandria and Patricia Higgins of Newport News, Virginia; six grandchildren; and 10 great-grandchildren.