Isan language

Isan or Northeastern Thai (autonym: ภาษาลาว/ພາສາລາວ, IPA: [pʰâː.sǎː lâːw]; Thai: ภาษาอีสาน, RTGS: Phasa Isan) refers to the local development of the Lao language in Thailand, after the political split of the Lao-speaking world at the Mekong River at the conclusion of the Franco-Siamese crisis of 1893. The language is still referred to as Lao by native speakers.

As a variety of the Lao language, Isan belongs to the Southwestern branch of Tai languages in the Kra-Dai language family. It is most closely related to (other than Lao) "tribal" Tai languages such as Phu Thai and Tai Yo. Isan is officially classified as a dialect of the Thai language by the Thai government. Although (Central) Thai is a closely related Southwestern Tai language, it falls within a different subbranch. Central Thai and Isan are mutually intelligible only with difficulty; even though they share over 80% cognate vocabulary, they have very different tonal patterns and vowel qualities, and many commonly used words in Isan differ from Thai, thus hampering comprehension.

The Lao language has had a long presence in Isan, arriving with migrants who followed the river valleys into Southeast Asia from southern China some time in the 8th to 10th centuries. The region of what is now Isan was nominally under the Lao kingdom of Lan Xang from 1354 to 1707. After the fall of Lan Xang, the Lao splinter kingdoms became tributary states of Siam. During the late 18th and much of the 19th century, Siamese soldiers carried out forced migrations of Lao people from the western bank of the Mekong River to the eastern bank, now Isan. As a result of these massive movements, Isan speakers comprise almost one-third of the population of Thailand and represent more than 80% of the population of Lao speakers overall. Isan is natively spoken by roughly 13-16 million people of the Isan region (2005), although the total population of speakers, including Isan people in other regions of Thailand and those that speak it as a second language, likely exceeds 22 million.

The Lao language in Thailand was preserved due to the Isan region's large population, mountains that separated the region from the rest of the country, a conservative culture and ethnic appreciation of local traditions. The language was officially banned from being referred to as the Lao language in official Thai documents at the turn of the 20th century. Assimilatory laws of the 1930s that promoted Thai nationalism, Central Thai culture and mandatory use of Standard Thai led to a diglossic situation with the region's inhabitants largely being bilingual and viewing themselves as Thai citizens. Isan is reserved as the language of the home, agrarian economy and provincial life. The Tai Noi script was also banned, thus making Isan a spoken language, although an ad hoc system of using Thai script and spelling of cognate words is used in informal communication.

Isan is also one of the poorest, least developed regions of Thailand, with many Isan people having little education, often employed as laborers, domestic workers, cooks, taxi drivers, and in other service jobs. Combined with historic open prejudice toward Isan people, this has fueled a negative perception of the language. Despite its vigorous usage, since the mid-20th century, the language has been undergoing a slow relexification by Thai or language shift to Thai altogether, threatening the vitality of the language. However, with attitudes toward regional cultures becoming more relaxed in the late 20th century onwards, increased research into the language by Thai academics at Isan universities and an ethno-political stance often at odds with Bangkok, some efforts to help stem the slow disappearance of the language are beginning to take root, fostered by a growing awareness and appreciation of local culture, literature and history.

As an umbrella term for the Lao varieties as spoken in Northeastern Thailand, Isan remains essentially the same as the Lao language of Laos, albeit nonetheless differentiated in orthography and some minor lexical elements. Both right and left bank varieties are most closely related to the other Lao-Phuthai (Lao-Phoutai) languages such as Phuthai (Phoutai) and Tai Yo (Tai Gno), all which are mutually intelligible to each other. The Lao-Phuthai languages are closely related and somewhat mutually intelligible with the other Southwestern branch Tai languages such as the Chiang Saen languages, which includes Standard Thai, and the Northwestern languages, comprising the speech of the Dai/Shan peoples. Lao and Thai, despite separate development, were pushed closer together due to proximity and adoption of the same Khmer, Sanskrit and Pali loan words. Lao is distantly related to the various Zhuang languages that comprise the Northern and Central branches of Tai languages, and even more distantly to the other Kra-Dai languages.

Within Thailand, Isan is officially classified as a 'Northeastern' dialect of the Thai language and is referred to as such in most official and academic works concerning the language produced in Thailand. The use of 'Northeastern Thai' to refer to the language is re-enforced internationally with the descriptors in the ISO 639-3 and Glottolog language codes. Outside of official and academic Thai contexts, Isan is usually classified as a particular sub-grouping of the Lao language such as by native speakers, Laotian Lao and many linguists, it is also classified as a separate language in light of its unique history and Thai-language influence, such as its classification in Glottolog and Ethnologue.

Isan people have traditionally referred to their speech as the Lao language (ภาษาลาว, ພາສາລາວ, [pʰâː.săː lâːw]). This is sometimes modified with the word tai (ไท, ໄທ, [tʰâj], lit. 'inhabitant' or 'person') or the related form Thai (ไทย, ໄທ, [tʰâj]), which refers to Thailand or the Thai people, thus yielding Phasa Tai Lao (ภาษาไทลาว, ພາສາໄທລາວ, 'language of the Lao people') and Phasa Thai Lao (ภาษาไทยลาว, ພາສາໄທລາວ, 'Lao language of Thailand').