[1][2] He was the first United States Ambassador to Upper Volta (now Burkina Faso), Dahomey (now Benin), Niger, and Ivory Coast (now Côte d'Ivoire) simultaneously.

On July 31, 1960, an envoy, Donald R. Norland, had presented his credentials as Chargé d'Affaires ad interim on the previous day of Reams' appointment.

Reams served as the specialist on Jewish issues for the State Department's Division of European Affairs during World War II.

In the role he downplayed reports of Nazi exterminations of Jews in Europe, casting doubts on diplomatic cables that sought to notify the United Nations and raise alarm.

Reams concluded the reports of mass deportation and murder were accurate, but wrote in 1942 that if the State Department corroborated such information, it would have exposed governments to "increased pressure... to do something.