Editing Molotov–Ribbentrop Pact (section)

===Initial invasions===
{{Main|Invasion of Poland|Soviet invasion of Poland}}
{{See also|German–Soviet military parade in Brest-Litovsk}}
On 1 September 1939, [[invasion of Poland|Germany invaded Poland]] from the west.<ref name="stalinswars82"/> Within a few days, Germany began conducting massacres of Polish and Jewish civilians and POWs,{{Sfn|Datner|1962|p=11}}<ref name="Garvin5">{{Cite book|first=JL|last=Garvin|title=German Atrocities in Poland|publisher=Free Europe|page=15}}.</ref> which took place in over 30 towns and villages in the first month of the German occupation.{{Sfn|Datner|Gumkowski|Leszczynski|1962|pp=127–34}}<ref name="Świekatowo0">{{Cite web|url=http://www.um-swiecie.pl/index_en.php?cid=142&unroll=142|archive-url=https://web.archive.org/web/20090331194029/http://www.um-swiecie.pl/index_en.php?cid=142&unroll=142|url-status=dead|archive-date=31 March 2009|title=Um Swiecie|place=[[Poland|PL]]}}.</ref><ref name="Gibert85">{{cite book|first=Martin|last=Gilbert|title=The Holocaust|publisher=Fontana|year=1990|isbn=0-00-637194-9|pages=85–88}}.</ref> The [[Luftwaffe]] also took part by strafing fleeing civilian refugees on roads and by carrying out a bombing campaign.{{Sfn|Davies|1986|p=437}}{{Sfn|Cyprian|Sawicki|1961|p=65}}{{Sfn|Datner|Gumkowski|Leszczynski|1962|p=18}} The Soviet Union assisted German air forces by allowing them to use signals broadcast by the Soviet radio station at [[Minsk]], allegedly "for urgent aeronautical experiments".<ref>АВП СССР, ф. 06, оп. 1, п. 8, д. 74, л. 20. л. 26. Item 4: "Hilger asked to pass the request of the German Air forces' Chief of Staff (the Germans wanted the radio station in Minsk, when it is idle, to start a continuous broadcast needed for urgent aeronautical experiments. This translation should contain the embedded call signs "Richard Wilhelm 1.0", and, in addition to that, to broadcast the word "Minsk" as frequent as possible. The Molotov's resolution on that document authorised broadcasting of the word "Minsk" only)."</ref>
Hitler declared at Danzig:
{{blockquote|Poland never will rise again in the [[Second Polish Republic|form]] of the [[Treaty of Versailles|Versailles treaty]]. That is guaranteed not only by [[Nazi Germany|Germany]], but also{{nbsp}}... [[Soviet Union|Russia]].<ref>{{cite news|url=https://time.com/vault/issue/1939-10-02/page/22/|title=Seven Years War?|work=[[TIME Magazine|Time]]|date=2 October 1939|access-date=26 January 2021|archive-date=18 September 2021|archive-url=https://web.archive.org/web/20210918024831/https://time.com/vault/issue/1939-10-02/page/22/|url-status=live}}</ref>}}

[[File:Davidlowrendezvous.png|thumb|left|Cartoon in the ''[[Evening Standard]]'' depicting Hitler greeting Stalin after the [[invasion of Poland]], with the words: "The scum of the earth, I believe?" To which Stalin replies: "The bloody assassin of the workers, I presume?";<ref>The cartoon is a parody of "[[Dr. Livingstone, I presume?]]", [[Henry Morton Stanley]]'s supposed greeting to Livingstone in November 1871. Artistic reconstructions of that event (see relevant articles) showed them raising their hats to one another in greeting.</ref> 20 September 1939.]]
[[File:Armia Czerwona, Wehrmacht 22.09.1939 wspólna parada.jpg|thumb|Common parade of Wehrmacht and Red Army in [[Brest (Belarus)|Brest]] at the end of the invasion of Poland. At the centre are Major General [[Heinz Guderian]] and Brigadier [[Semyon Krivoshein]].]]

In the opinion of [[Robert Service (historian)|Robert Service]], Stalin did not move instantly but was waiting to see whether the Germans would halt within the agreed area, and the Soviet Union also needed to secure the frontier in the [[Soviet–Japanese border conflicts]].{{Sfn|Service|2003|p=256}} On 17 September, the [[Red Army]] [[Soviet invasion of Poland|invaded Poland]], violating the 1932 [[Soviet–Polish Non-Aggression Pact]], and occupied the Polish territory assigned to it by the Molotov–Ribbentrop Pact. That was followed by co-ordination with German forces in Poland.{{Sfn|Roberts|2006|p=43}} Polish troops already fighting much stronger German forces on its west desperately tried to delay the capture of Warsaw. Consequently, Polish forces could not mount significant resistance against the Soviets.<ref>{{cite book|last=Zaloga|first=Steven J|title=Poland 1939|url=https://archive.org/details/polandbirthblitz00zalo|url-access=limited|publisher=Osprey|place=Botley, UK|year=2002|page=[https://archive.org/details/polandbirthblitz00zalo/page/n72 80]|isbn=9781846035623}}.</ref> On 18 September, ''[[The New York Times]]'' published an editorial arguing that "Hitlerism is brown communism, Stalinism is [[red fascism]]...The world will now understand that the only real 'ideological' issue is one between democracy, liberty and peace on the one hand and [[despotism]], terror and war on the other."<ref>{{cite news|url=https://www.nytimes.com/1939/09/18/archives/the-russian-betrayal.html|title=The Russian Betrayal|date=18 September 1939|newspaper=The New York Times|access-date=11 February 2020|issn=0362-4331|url-access=subscription|archive-date=21 October 2021|archive-url=https://web.archive.org/web/20211021090823/https://www.nytimes.com/1939/09/18/archives/the-russian-betrayal.html|url-status=live}}</ref>

On 21 September, Marshal of the Soviet Union [[Kliment Voroshilov|Voroshilov]], German military attaché General [[Ernst August Köstring|Köstring]], and other officers signed a formal agreement in Moscow co-ordinating military movements in Poland, including the "purging" of saboteurs and the Red Army assisting with destruction of the "enemy".{{Sfn|Nekrich|Ulam|Freeze|1997|p=130}} Joint German–Soviet parades were held in [[Lviv]] and [[Brest-Litovsk]], and the countries' military commanders met in the latter city.{{Sfn|Nekrich|Ulam|Freeze|1997|p=131}} Stalin had decided in August that he was going to liquidate the Polish state, and a German–Soviet meeting in September addressed the future structure of the "Polish region".{{Sfn|Nekrich|Ulam|Freeze|1997|p=131}} Soviet authorities immediately started a campaign of [[Sovietisation]]<ref name="Sowietyzacja">{{cite book|language=pl|title=Sowietyzacja Kresów Wschodnich II Rzeczypospolitej po 17 września 1939|year=1998|editor-first=Adam|editor-last=Sudoł|page=441|publisher=Wyższa Szkoła Pedagogiczna|location=Bydgoszcz|isbn=83-7096-281-5}}</ref><ref name="Relocation">{{cite book|title=Demography and National Security|year=2001|editor1-first=Myron|editor1-last=Weiner|editor2-first=Sharon Stanton|editor2-last=Russell|pages=308–15|chapter=Stalinist Forced Relocation Policies|chapter-url=https://books.google.com/books?id=J9nuv7MGQ5MC&q=Sovietization&pg=PA309|publisher=Berghahn Books|isbn=1-57181-339-X}}</ref> of the newly acquired areas. The Soviets organised staged elections,<ref name="Elections">{{cite web|language=pl|first=Bartłomiej|last=Kozłowski|title="Wybory" do Zgromadzeń Ludowych Zachodniej Ukrainy i Zachodniej Białorusi|publisher=[[Naukowa i Akademicka Sieć Komputerowa|NASK]]|year=2005|work=Polska|location=[[Poland|PL]]|url=http://wiadomosci.polska.pl/kalendarz/kalendarium/article.htm?id=132394|access-date=13 March 2006|url-status=dead|archive-url=https://web.archive.org/web/20060628125314/http://wiadomosci.polska.pl/kalendarz/kalendarium/article.htm?id=132394|archive-date=28 June 2006}}</ref> the result of which was to become a legitimisation of the Soviet annexation of eastern Poland.<ref name="Revolution">{{cite book|first=Jan Tomasz|last=Gross|title=Revolution from Abroad|year=2003|page=396|publisher=Princeton University Press|location =Princeton|isbn=0-691-09603-1|author-link=Jan Tomasz Gross|url=https://books.google.com/books?id=XKtOr4EXOWwC&q=October+22+1939&pg=PA71}}.</ref>