This collection of studies is devoted to the social role of language in the history of East Central Europe from the Middle Ages to the beginning of the 20th century. The authors examine the specificity of East Central Europe, an area that was a borderland between \'West\' and \'East\'. The region was largely inhabited by Slavic people, which gave it the character - and sometimes the name - of a Slavic world, but it was also home to non-Slavic ethnic groups (Germans, Hungarians, Jews). Various cultures, traditions, religions, faiths reinforced by social and economic divisions, as well as changing political borders over the centuries, created a complex picture of human relations. The authors set out to understand the history of East Central Europe through language - or rather co-existing languages - and the role they played at different levels of communication and in different systems of human relations (social, economic and political).