Plans of defence and measures by Lithuanian army to repulse the possible Polish agression in 1921–1937

Documentary material and its analysis provided in this article assuredly confirms propositions published in work of previous researchers of Lithuanian past (politics, diplomats, scientists, etc.) that during the discussed period implemented that politics of ruling circles of neighbouring Poland were aggressive and had plans of annexation towards Lithuania. It was like this from the start when these two neighbouring countries regained their statehood and lasted up until their fall in the end of fourth decade of 20th century. Such aggressiveness of Polish was evidenced the most in political and military spheres. Polish government, treating Lithuania as only temporary country during the whole mentioned period was taking all the measures to not only fixate in Vilnius Region, but also made aggressive plans and actions in order to subjugate whole Lithuania. Exceptional role, when solving the mentioned goal, was given to numerous Polish organizations of military nature as well as to parts or regular army concentrated in Vilnius Region and near it. These Polish armed forces were given a task to implement various provocations against Lithuania and to prepare for possible military actions. Leadership of Lithuanian army during the discussed period of 1921–1926 because of the clearly expressed aggressive politics that Polish were establishing was forced to systematically strengthen their potential of military forces, try to defend with the force of gun the neutral zone of Valkininkai-Rūdiškiai railway section, at the beginning of 1923, and at the end of this period, to prepare thorough, well-motivated defence plans to reform armed forces, adjusting them to the changed conditions. Unfortunately, because of the changed circumstances inside the region, it was not possible to realize them. After the revolution of the country on 17th of December, 1927 when nationalist leaders known for their anti-Polish attitudes came into government, disagreement between Lithuania and Poland became even worse. Possible threat of Polish aggression was getting bigger, using political emigrants of Lithuanians named "plečkaitininkai". During this period many distinct changes appeared even in the office of Lithuanian army itself. Many talented officers joined its side, who had finished their higher education in war academies of foreign countries, as well as schools of their own country. By taking leading positions in army headquarters, its departments as well as in divisions and army parts of various kinds, they, when there were cases of necessity, managed to prepare for the chiefs concrete operative ideas, various directives, instructions, plans and other important documents, which would be needed to use in case Polish would attack them. In order to improve fighting preparation of the army, each year manoeuvres of various degrees were held. At the end of this period experimental mobilizations were started to be practised. It was managed to noticeably improve armament of the army as well as its material support. The factor that made rapidly improve defensive force of the army was that from spring of 1937, Polish started provocative action by the administrative line. Even though they did not turn out into armed conflict that year, but on 18th of March, 1938, Lithuanian government was forced to accept ultimatum of Poland about contracting diplomatic relations with it, without any preparation. With this ultimatum Polish confirmed their imperialistic devices towards Lithuania and a wish to solve it with military forces