This paper gives a survey of the linguistic situation in northern Europe in the late Middle Ages. It is based on three earlier research projects and summarises some of their results, especially as far as language choice and domains are concerned. The focus lies, however, on the development, role and function of receptive as opposed to productive bi-/multilingualism and language standardisation. On the basis of Peter Trudgill’s terminology of language contact, new terms for differentiating forms of linguistic convergence and divergence are proposed. Three case studies highlight the role receptive multilingualism plays for adult German learners of (eastern) Scandinavian languages, focusing on the form of the definite article, the use of the periphrastic genitive and the overlooking of V1-patterns in declarative sentences.