The United States recognized The Gambia on February 18, 1965, when Assistant Secretary for African Affairs G. Mennen Williams represented President Lyndon B. Johnson as his Personal Representative with the rank of Special Ambassador at the ceremonies marking the independence of Gambia held at the capital, Bathurst. The Gambia previously had been under British sovereignty.

Diplomatic relations were established on August 9, 1965, when Ambassador Mercer Cook presented his credentials to Gambian authorities. Cook also was accredited to Senegal and was resident at Dakar.

The Embassy at Bathurst (now Banjul) was established on September 9, 1965, with John G. Gossett as Chargé d'Affaires ad interim.