John Louis O’Sullivan (1813–1895)

State of Residence: New York
  1. Chargé d’Affaires (Portugal)
    Appointed: February 16, 1854
    Presentation of Credentials: June 16, 1854
    Termination of Mission: Promoted to Minister Resident October 19, 1854
    • Nominated February 25, 1856, to be Envoy Extraordinary and Minister Plenipotentiary; nomination withdrawn before the Senate acted upon it.
  2. Minister Resident (Portugal)
    Appointed: June 29, 1854
    Presentation of Credentials: October 19, 1854
    Termination of Mission: Presented recall on July 15, 1858
  3. Envoy Extraordinary and Minister Plenipotentiary (Portugal)
    • Nomination of February 25, 1856, withdrawn before the Senate acted upon it.