Inspired by sociolinguistic scholarship, this study examines the influence of linguistic vitality, the social health of a language, on perceived in-group threat and out-group attitudes. Using an experimental design that manipulated perceptions of the linguistic vitality of French in Quebec, this study sought to ascertain the causal role of linguistic vitality on intergroup attitudes. The results demonstrate that the type of information, positive or negative, about linguistic vitality influences perceptions of threat towards a language. However, results about linguistic vitality information's impact on out-group attitudes, support for independence and subjective identity revealed inter-individual heterogeneity.