The article examines the Russian-Mari linguistic environment, focusing on the usage of the Russian and Mari languages (Meadow Mari and Hill Mari), identifying the level of bilingualism in the context of the widespread use of the Russian language and the relationships between language practices and ethnic identity. This comprehensive interdisciplinary ethnological-linguistic study employs various methodological approaches. The research data were collected through a survey conducted using the Texas University “Bilingual Language Profi le” questionnaire, supplemented by several blocks of questions on ethno-social topics, as well as interviews with representatives of the linguistic environment. The data were collected during an ethnological expedition by the Faculty of History of Lomonosov Moscow State University in the Republic of Mari El (Zvenigovsky, Kuzhenersky, Medvedevsky, Morkinsky, Orshansky, Sernursky, Sovietsky districts, and the city of Yoshkar-Ola). The majority of the 70 respondents identify themselves as belonging to the ethnographic group of Meadow Mari, with some also speaking Hill Mari. They share a deep involvement in Mari culture, being (or having been) employees of cultural centers and museums, librarians, school teachers, researchers of Mari culture, active participants in local communities, folklore ensembles, and thematic communities on social networks. Most of them can be classifi ed as ethnic activists. The study employed both qualitative (analysis of the collected interviews) and quantitative (analysis and graphical representation of the collected survey data) methods. The research revealed a high degree of interest among the Mari people in preserving their ethnic languages alongside traditional culture and identity. Additionally, the survey data indicate a relatively balanced level of Russian-Mari bilingualism, especially among those over 30 years old. Among the younger generation, there is a noticeable “shift ” in bilingualism towards the Russian language, likely due to the Russian-speaking educational environment.