One of the venues where group interests and group ideas could be expressed in the early modern era was the churches. Conflict potential was offered not only by religion itself, but - as in the case of Český Krumlov/Krumau in Southern Bohemia - language as well.
Attempts by parish representatives, in the end unsuccessful, to get German-language sermon transferred from a smaller to the large church of the town parish have brought about a unique source: In the middle of the 17th and at the beginning of the 18th century listings were compiled of the whole town population by language. The question in what language sermons should be delivered led to heated debates between a multitude of actors - from rural and town residents through local clergy, representatives of town and local reign to the sovereign and his administration.
The present study looks at the two lists and connected files from the perspective of which kind of personal or group identification with a given language was expressed. The author reaches the conclusion that, as early as the 17th century, the notion of nation was closely related to language, even in a non-academic environment.