A Guide to the United States’ History of Recognition, Diplomatic, and Consular Relations, by Country, since 1776: Thailand


Thailand was one of the only countries in South and Southeast Asia that avoided colonization during the nineteenth century. The United States and Thailand’s first official diplomatic interaction occurred in 1833 when they signed a Treaty of Amity and Commerce, which was the United States’ first treaty with an Asian country. Since the end of World War II, the United States and Thailand have developed close relations.

Modern Flag of Thailand


First Official Diplomatic Interaction, 1833.

The United States and Thailand engaged in their first official diplomatic interaction on March 20, 1833, when they signed a Treaty of Amity and Commerce. Edmund Roberts, who negotiated this treaty during a mission to the Far East as Special Agent of the United States, received instructions dated January 27, 1832, that directed him to negotiate treaties with Cochinchina, Siam, and the powers of Arabia on the Red Sea.

Consular Presence

Establishment of Consular Relations, 1859.

John Hassett Chandler became the Acting Vice Consul in Charge on January 25, 1859.

Diplomatic Relations

Establishment of Diplomatic Relations and the American Legation in Siam, 1882.

Diplomatic relations and the first U.S. Legation in Thailand (then Siam) were established on October 23, 1882, when John A. Halderman presented his credentials as Minister Resident and Consul General.

Elevation of American Legation to Embassy Status, 1947.

On April 10, 1947, Edwin F. Stanton was promoted to become the first U.S. Ambassador to Thailand. Stanton presented his credentials on May 9, 1947.

Treaties and Agreements

Treaty of Amnity and Commerce, 1836.

The United States and Thailand signed a Treaty of Amity and Commerce on March 20, 1833 in Bangkok. Following ratification by both countries, ratifications were exchanged at Bangkok on April 14, 1836.


  • Department of State Country Fact Sheet: Thailand
  • Department of State Country Information: Thailand
  • Thailand: A Country Study, Compiled by the Federal Research Division of the Library of Congress and edited by Barbara Leitch LePoer (1989)
  • Treaties and Other International Agreements of the United States of America, 1776-1949, Compiled under the direction of Charles I. Bevans, (DOS, 1974), vol. 11, pp. 978-1042.
  • Treaties and Other International Acts of the United States of America, edited by Hunter Miller (Washington: US GPO, 1933), vol. 3, Document 76, pp. 741-788.