Gerber, PascalPascalGerber2026-02-112026-02-11https://boris-portal.unibe.ch/handle/20.500.12422/231708The Upper Arun languages are a small group of critically endangered languages that belong to the Kiranti branch of the Trans-Himalayan (= Sino-Tibetan) language family and are spoken in the Koshi Province of eastern Nepal. The group comprises the three languages Mewahang, Lohorung and Yamphu. This dissertation constitutes the first ever historical-comparative study of the Upper Arun languages within the framework of the comparative method. It first offers a detailed treatment of the historical phonology of the Upper Arun languages. This then serves as the foundation for the comparison and reconstruction of parts of the nominal and verbal morphology, i.e. pronouns and demonstratives, nominal case morphology, verb stem alternations and verbal inflectional morphology, including the hallmark of Kiranti languages, the complex argument indexation morphology. The strict application of the comparative method and in particular the consideration of analogy as an explanatory tool allow for a precise and explicit reconstruction of a considerable number of Proto-Upper Arun morphemes. In addition to the historical-comparative main part, this dissertation contains a descriptive sketch of the previously largely undocumented western dialect of Mewahang. The data for this come from field work conducted in the speaking area between 2017 and 2022. Furthermore, the appendix of the dissertation presents the Mewahang and Lohorung data collected by Brian Houghton Hodgson in the 19th century (the earliest accessible source on the Kiranti languages) and provides detailed annotations in light of modern-day data. This does not only include the published word lists (Hodgson 1857), but also extensive unpublished, handwritten materials on Lohorung that are made available here in digitalized form for the first time.de400 - Language::490 - Other languagesthesis10.48620/94570urn:nbn:ch:bel-bes-12243