This article presents a comprehensive reconstruction of the origin of the toponym Zangezur, based on evidence from Sasanian sigillography, Armenian toponymy, historical hydronymy, and comparative-historical linguistics. The point of departure is a Sasanian administrative bulla of the sixth century CE, in which the toponym Marz-ī Zangāvan is attested for the first time as an independent Sasanian administrative-territorial unit. This form constitutes the earliest known written attestation of the component Zang- in the South Caucasus region.
The article proposes a new interpretation of the toponym Marz-ī Zangāvan. On the basis of historical-geographical and toponymic evidence, it is argued that Zangāvan originally functioned as a hydronym—the name of the largest river of historical Zangezur, known in the Armenian tradition as the Vorotan. Historical sources attest several names for this river system (Vorotan, Vorot, Orot, Barkušat (var. Bargušad), Bazarçay (^*Basarçay), Rut, Urud, etc.), testifying to the long coexistence of diverse linguistic traditions in the naming of this waterway. Among the Iranian parallels, particular significance attaches to the hydronym Āb-e Zangāvan (also known as Rūdkhāneh-ye Čam Zangavān or Rūd-e Pīvanān) in Ilam Province, Western Iran, demonstrating that the form Zangāvan genuinely functioned in the Iranian tradition as a river name.
The second part of the study is devoted to the reconstruction of the Armenian proto-form Zang-i jor (“the gorge of sound”/“ringing gorge”) and the analysis of its subsequent Persian administrative adaptation ^*Zang-e zūr, as well as the later Turkic adaptation Zəngəzur (var. Zangazur-which is a Persian distorted or reinterpreted form!). The proposed reconstruction is the first to unite evidence from sigillography, historical hydronymy, Armenian word-formation patterns, and Persian and Turkic administrative traditions into a unified explanatory system for the origin of the toponym.