Perlis was once a part of the Kedah. After Kedah was conquered by Thailand in 1821, Perlis was seperated from Kedah. The Thais established Perlis as a vassal sate under the care of Syed Hussein. The Anglo-Siamese Treaty of 1909 transferred Thai sovereignty over Perlis to the Btitish.
In World War II, the Japanese “returned” Perlis to Thailand during the Japanese Occupation in Malaysia. After the war, Perlis again came under the protection of the British until it gained independence with the formation of the Federation of Malaya in 1957.