ENIn 1937, Zenonas Ivinskis, a historian and associate professor at Vytautas Magnus University, stated that The publication of Lithuanian history sources has, until now, you could say, been driven by the initiative and concern of one person ... The rich past of the Lithuanian nation hardly has any of its own documents in present-day [interwar] Lithuania. There are plenty in the archives of Poland and Königsberg, in Riga and Tartu, in Danzig, and even in Berlin. And letʼs not forget what an inexhaustible source the Vatican archive is! An important task in the science of history in Lithuania is to publish and register the Lithuania-related material now found elsewhere. Regardless of the fact that nine decades have passed since the interwar years, when Lithuaniaʼs historians raised these ideas and outlined what needed to be done, source research remains and will continue to remain a relevant field of activity for historians, as new and hitherto unknown or unnoticed sources are always emerging. New relevant themes and aspects always arise in society, which steer interest to certain documents and groups. The Lithuanian Institute of History publicly declares its mission as follows: By developing fundamental and applied research, to study the evolution of the Lithuanian nation, Lithuaniaʼs society, its culture, economy and statehood, to gather, systematise and spread the documentary and the intangible historical heritage. Thus, this publication is one of the instituteʼs tasks in implementing its mission. It joins the broader block of sources relating to relations between Lithuania and Soviet Russia (the Soviet Union).A few years ago, in 2020, a collection of documents was published by the Lithuanian Institute of History with documents from 1917 to 1920. This is a rather important period, as it was when the question of the existence of a state dominated by the modern Lithuanian nation was determined. Partial success (defended sovereignty in the territory, albeit without its capital in Vilnius) was indeed a breakthrough that determined everything that unfolded in the next century and continues to happen today. In the 21st century, the border that today runs between the former Soviet Russia (later the Soviet Union), the successor of the rights of the Russian Empire, and the countries that earned their newly won independence after the First World War, is noted as an approximate boundary separating EU and Nato countries from those lying further east. [Extract, p. 213-214]