The United States recognized Sao Tome and Principe in 1975.
Modern Flag of Sao Tome and Principe
The United States recognized the Democratic Republic of Sao Tome and Principe on July 12, 1975, when President Gerald R. Ford sent a letter to that effect to President Manuel Pinto de Costa. Sao Tome and Principe previously had been under Portuguese sovereignty
The United States and Sao Tome and Principe established diplomatic relations on February 14, 1976, when Ambassador Andrew L. Steigman presented his credentials to the government at Sao Tome. Steigman also was accredited to Gabon and was resident at Libreville. No mission has been established at Sao Tome.