Time Frame and Process of Language Decline in Displaced Tai Yuan:  Studies from Ancient Manuscripts

Yuttaporn Naksuk

doi:10.66815/ejecs/2675

Authors

Yuttaporn Naksuk Research Institute for Languages and Cultures of Asia, Mahidol University, Thailand https://orcid.org/0009-0001-5998-314X

DOI:

https://doi.org/10.66815/ejecs/2675

Keywords:

language decline, Tai Yuan language, ancient manuscripts, displaced community

Abstract

Approximately 5,000 Tai Yuan people live among Central Thai speakers in Don Rae Sub-district, Mueang Ratchaburi District, Ratchaburi Province, Central Thailand. Their ancestors were displaced from Chiang Saen (in present-day northern Thailand), following the Burmese Siamese War in 1804. After more than two centuries living alongside the Central Thai-speaking majority, the Tai Yuan language has inevitably been influenced by the dominant language. This study examines the time frame and process of language decline in the Tai Yuan community of Don Rae Sub-district following migration, using evidence from linguistic changes and cultural changes in traditional scribal conventions. It draws on data from colophons of 56 Tai Yuan palm-leaf manuscripts preserved in Don Rae Sub-district. Linguistic and palaeographic approaches are employed to analyze changes in phonology, lexicon, orthography, letterforms, and dating conventions. The results show that, in the first 50 years after migration, no clear evidence of language decline is observed. Around 50-60 years after migration, Central Thai influence emerged through loanwords and a shared month-counting system, followed by gradual changes in orthography, letterforms, and phonology under the influence of Thai and Dhamma Lao scripts. The Lan Na-based month system later faded and was replaced by the official Siamese calendar. By approximately 150 years after migration, the Tai Yuan script had completely disappeared from written evidence, reflecting a gradual, multi-dimensional language decline affecting both linguistic features and the writing system. This study proposes a manuscript-based chronological model for analyzing language decline in displaced communities, offering insights into language maintenance and revitalization.

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Author Biography

Yuttaporn Naksuk, Research Institute for Languages and Cultures of Asia, Mahidol University, Thailand

is an assistant professor at the Research Institute for Languages and Cultures of Asia, Mahidol University, Thailand. His expertise lies in Tai linguistics and ancient Tai scripts. His research focuses on the languages and cultures of Tai ethnic groups in Thailand, Laos, and Myanmar. He teaches and supervises students in Tai epigraphy, dialectology, historical linguistics, and Burmese language and linguistics.

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