Katyn massacreThe Katyn massacre was a series of mass executions of nearly 22,000 Polish military officers and intelligentsia prisoners of war carried out by the Soviet Union, specifically the NKVD ("People's Commissariat for Internal Affairs", the Soviet secret police) in April and May 1940. Though the killings also occurred in the Kalinin and Kharkiv prisons and elsewhere, the massacre is named after the Katyn forest, where some of the mass graves were first discovered by German Nazi forces.
Waffen-SSThe Waffen-SS (ˈvafn̩ʔɛsˌʔɛs) (Armed SS) was the combat branch of the Nazi Party's paramilitary Schutzstaffel (SS) organisation. Its formations included men from Nazi Germany, along with volunteers and conscripts from both occupied and unoccupied lands. The Waffen-SS grew from three regiments to over 38 divisions during World War II, and served alongside the German Army (Heer), Ordnungspolizei (Order Police), and other security units.
Guerrilla warfareGuerrilla warfare is a form of unconventional warfare in which small groups of irregular military, such as rebels, partisans, paramilitary personnel or armed civilians including recruited children, use ambushes, sabotage, terrorism, raids, petty warfare or hit-and-run tactics in a rebellion, in a violent conflict, in a war or in a civil war to fight against regular military, police or rival insurgent forces. Although the term "guerrilla warfare" was coined in the context of the Peninsular War in the 19th century, the tactical methods of guerrilla warfare have long been in use.
Occupation of the Baltic statesThe three independent Baltic countries – Estonia, Latvia, and Lithuania – were invaded and occupied in June 1940 by the Soviet Union, under the leadership of Stalin and auspices of the Molotov–Ribbentrop Pact that had been signed between Nazi Germany and the Soviet Union in August 1939, immediately before the outbreak of World War II. The three countries were then annexed into the Soviet Union (formally as "constituent republics") in August 1940. The United States and most other Western countries never recognised this incorporation, considering it illegal.
Eastern Front (World War II)The Eastern Front of World War II was a theatre of conflict between the European Axis powers against the Soviet Union (USSR), Poland and other Allies, which encompassed Central Europe, Eastern Europe, Northeast Europe (Baltics), and Southeast Europe (Balkans) from 22 June 1941 to 9 May 1945. Of the estimated 70–85 million deaths attributed to World War II, around 30 million occurred on the Eastern Front, including 9 million children.
VilniusVilnius (ˈvɪlniəs , ˈvjɪljnjʊs; previously known in English as Vilna, see other names) is the capital and the largest city of Lithuania, with a population of 593,436 . The population of Vilnius's functional urban area, which stretches beyond the city limits, is estimated at 718,507 (as of 2020), while according to the Vilnius territorial health insurance fund, there were 753,875 permanent inhabitants as of November 2022 in Vilnius city and Vilnius district municipalities combined.
Jewish partisansJewish partisans were fighters in irregular military groups participating in the Jewish resistance movement against Nazi Germany and its collaborators during World War II. A number of Jewish partisan groups operated across Nazi-occupied Europe, some made up of a few escapees from the Jewish ghettos or concentration camps, while others, such as Bielski partisans, numbered in the hundreds and included women and children. They were most numerous in Eastern Europe, but groups also existed in occupied France and Belgium, where they worked with the local resistance.