Bilingual practices and language shift in multiethnic convergence regions: a case study of Tianzhu Tibetan Autonomous County

This study examines bilingual practices and language shift (LS) in Tianzhu Tibetan Autonomous County, a multiethnic convergence region in northwestern China. Using questionnaires (n = 395), semi-structured interviews, and supplementary ethnographic observations, it investigates residents' language use, proficiency, and attitudes toward Tibetan, Standard Mandarin, and the Tianzhu Chinese dialect. Results reveal a two-stage LS trajectory: first from Tibetan to the Tianzhu dialect, and subsequently from the Tianzhu dialect to Mandarin. Tibetan has largely retreated from everyday communication, surviving mainly in religious domains, while the Tianzhu dialect itself is eroding among younger generations. Urban–rural contrasts highlight spatial variation in LS, with Mandarin dominating more rapidly in semi-urban centres than in rural settlements. Positive attitudes toward Mandarin, reinforced by educational and economic opportunities and national policies, further accelerate this transition. While Tibetan retains cultural and symbolic value, its communicative role is diminishing. By situating Tianzhu within broader debates on language contact, multilingual sustainability, and minority language shift, this study shows how ethnic integration and state policies reshape bilingualism in multiethnic regions and provides insights for inclusive language planning.