Looking Back: 175 Years of Relations
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Letter from King Mongkut, |
This year marks the 175th anniversary of the establishment of formal relations between the United States and Thailand. This special friendship goes back to March 20, 1833 when the United States and Thailand, then Siam, signed the Treaty of Amity and Commerce. The Treaty of 1833 was the United States’ first treaty with a country in Asia, making Thailand truly our oldest friend in the region.
We invite you to learn more about the long and special history of U.S.-Thai relations through the information and resources presented here.
- Timeline of Key Events in U.S.-Thai Relations
- Spotlight on the Treaty of Amity and Commerce of 1833
- U.S. Ambassadors to Thailand (1882 – Present)
- Thai Ambassador to the United States (1881- Present) English || Thai
- Official States Visits Over the Years
For more useful information on the history of U.S.-Thai relations, please visit our reading room.





