The article analyzes the issue of East Prussian meanings in the environment of Prussian Lithuanians in terms of their “mental maps” and “symbolical geography”. Particular attention is paid to the analysis of the communication channels that affected the process of mental appropriation of “our own region” – East Prussia – by the ethnic group of Prussian Lithuanians. The significance of the historical tradition related to the reformationist provision of protection of the status of the Lithuanian language in churches and schools of Prussian Lithuania, as well as of the periodicals published in Lithuanian at the turn of the 20th c. in East Prussia, is emphasized, as it is considered to be a significant communication channel that formed the conception of East Prussia, a close and “one’s own” space from the geographical, administrative-political, and civilization viewpoints. The analysis is oriented towards the problem of “appropriation of the past”, and it contributes to the understanding how the meanings of East Prussia topical for Prussian Lithuanians formed and which symbols marked the presently imaginary spaces identified with East Prussia and Prussian Lithuania/ Lithuania Minor as its part.