Northeastern Thailand

Isan (Isan/Thai: อีสาน, pronounced [ʔīː.sǎːn]; also written as Isaan, Isarn, Issarn, Issan, Esan, or Esarn; from Pali ऐशान aiśāna or Sanskrit ऐशान aiśāna "Northeast") consists of 20 provinces in the northeastern region of Thailand. Isan is Thailand's largest region, located on the Khorat Plateau, bordered by the Mekong River (along the border with Laos) to the north and east, by Cambodia to the southeast and the Sankamphaeng Range south of Nakhon Ratchasima. To the west it is separated from northern and central Thailand by the Phetchabun Mountains.

Since the beginning of the 20th century, northeastern Thailand has been generally known as Isan, while in official contexts the term phak tawan-ok-chiang-nuea (ภาคตะวันออกเฉียงเหนือ; "northeastern region") may be used. The term "Isan" was derived from Isanapura, the capital of the Chenla Kingdom. The majority Lao-speaking population of the region distinguish themselves not only from the Lao of Laos but also from the central Thai by calling themselves khon Isan or Thai Isan in general. However, some refer to themselves as simply Lao, and academics have recently been referring to them as Lao Isan or as Thai Lao, with the main issue with self-identification as Lao being stigma associated with the Lao identity within Thai society. The Khmer-speaking minority and the Kuy people ("Soui"), who live in the south of Isan, speak Austroasiatic languages and follow customs more similar to those of Cambodia than to those of the Thai and Lao, who are Tai peoples.

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