The Burney Treaty, so named after Henry Burney, head emissary from the East India Company, and known in Siamese history as the Treaty of Amity and Commerce (Siam–UK), was concluded with King Rama III in the latter part of 1826. This followed Dr. John Crawfurd's 1822 mission to the court of King Rama II, the principle objective of which was to determine Siam's position on the Malay states. The treaty acknowledged Siamese claims over the four northern Malay states of Kedah, Kelantan, Perlis and Terengganu. The treaty further guaranteed British possession of Penang and their rights to trade in Kelantan and Terengganu without Siamese interference. The four Malay states were not represented in the treaty negotiation. In 1909, the parties of the agreement signed a new treaty that superseded the 1826 treaty. The 1909 treaty, known as Anglo-Siamese Treaty of 1909, also known as the Bangkok Treaty of 1909, transferred the four Malay states from Siamese to British dominion.
^Stern, Duncan (May 14 – May 20, 2004). "Dr. John Crawfurd and the Mission to Thailand, 1822" (Column). A Slice of Thai History. Pattaya Mail. Retrieved August 11, 2011. "This in turn helped Captain Henry Burney conclude a treaty of commerce with Thailand in June 1826."Check date values in: |date= (help)