Editing Axis powers (section)

===Soviet Union===
[[File:Bundesarchiv Bild 101I-121-0011-20, Polen, deutsch-sowjetische Siegesparade.jpg|thumb|upright|German and Soviet soldiers during the official transfer of [[Brest, Belarus|Brest]] to Soviet control in front of picture of Stalin, in the aftermath of the invasion and [[Partitions of Poland#"Fourth Partition"|partition of Poland]] by Nazi Germany and the Soviet Union in 1939]]{{See also|Germany–Soviet Union relations, 1918–1941|German–Soviet Axis talks|Molotov–Ribbentrop Pact|Soviet invasion of Poland}}
 
In 1939 the Soviet Union considered forming an alliance with either [[Molotov–Ribbentrop Pact negotiations|Britain and France]] or with Germany.<ref>{{Cite book|last=Nekrich, A. M. (Aleksandr Moiseevich)|url=https://www.worldcat.org/oclc/36023920|title=Pariahs, partners, predators : German-Soviet relations, 1922–1941|year=1997|publisher=Columbia University Press|others=Freeze, Gregory L., 1945–|isbn=0-231-10676-9|location=New York|pages=112–120|oclc=36023920}}</ref>{{sfn|Shirer|1960|pp=495-496}} When negotiations with Britain and France failed, they turned to Germany and signed the Molotov–Ribbentrop Pact in August 1939. Germany was now freed from the risk of war with the Soviets, and was assured a supply of oil. This included a secret protocol whereby territories controlled by [[Second Polish Republic|Poland]], Finland, [[Estonia]], [[Kingdom of Romania|Romania]], [[Latvia]] and [[Lithuania]] were divided into [[spheres of interest]] of the parties.<ref>{{Cite web|title=Internet History Sourcebooks|url=https://sourcebooks.fordham.edu/mod/1939pact.asp|access-date=2020-10-29|website=sourcebooks.fordham.edu}}</ref> The Soviet Union sought to re-annex some of territories that were under control of those states, formerly acquired by the [[Russian Empire]] in the centuries prior and lost to Russia in the [[aftermath of World War I]]; that included land such as the [[Kresy]] (Western [[Belarus]] and Western Ukraine) region ceded to Poland after losing the [[Soviet-Polish War]] of 1919–1921.<ref>Eastern Europe, Russia and Central Asia 2004, Vol. 4. London, England: Europa Publications, 2003. pp. 138–139.</ref>

On 1 September, barely a week after the pact had been signed, [[Invasion of Poland|Germany invaded Poland]]. The Soviet Union [[Soviet invasion of Poland|invaded Poland from the east]] on 17 September and on 28 September signed a [[German-Soviet Frontier Treaty|secret treaty]] with Nazi Germany to coordinate fighting against the [[Polish resistance movement in World War II|Polish resistance]]. The Soviets targeted intelligence, entrepreneurs and officers with mass arrests, with many victims sent to the [[Gulag]] in Siberia, committing a string of atrocities that culminated in the [[Katyn massacre]].<ref>{{cite web|url=http://avalon.law.yale.edu/subject_menus/nazsov.asp|title=Avalon Project – Nazi-Soviet Relations 1939–1941|website=avalon.law.yale.edu}}</ref> Soon after the invasion of Poland, the Soviet Union [[Occupation of Baltic Republics|occupied the Baltic countries]] of Estonia, Latvia and Lithuania,{{sfn|Senn|2007|p={{page needed|date=March 2012}}}}{{sfn|Wettig|2008|pp=20–21}} and annexed [[Bessarabia]] and [[Bukovina|Northern Bukovina]] from Romania. The Soviet Union attacked Finland on 30 November 1939, which started the [[Winter War]].{{sfn|Kennedy-Pipe|1995|p={{page needed|date=March 2012}}}} Finnish defenses prevented an all-out invasion, resulting in an [[Moscow Peace Treaty|interim peace]], but Finland was forced to cede strategically important border areas near [[Leningrad]].

The Soviet Union provided material support to Germany in the war effort against Western Europe through a pair of commercial agreements, [[German-Soviet Commercial Agreement (1939)|the first]] in 1939 and [[German-Soviet Commercial Agreement (1940)|the second]] in 1940, which involved exports of raw materials ([[phosphates]], [[chromium]] and [[iron ore]], [[mineral oil]], grain, cotton, and rubber). These and other export goods transported through Soviet and occupied Polish territories allowed Germany to circumvent the British naval blockade. In October and November 1940, [[German–Soviet Axis talks|German–Soviet talks]] about the potential of joining the Axis took place in Berlin.{{sfn|Roberts|2006|p=58}}{{sfn|Brackman|2001|pp=341–343}} [[Joseph Stalin]] later personally countered with a separate proposal in a letter on 25 November that contained several secret protocols, including that "the area south of [[Batum]] and [[Baku]] in the general direction of the [[Persian Gulf]] is recognized as the center of aspirations of the Soviet Union", referring to an area approximating present day Iraq and Iran, and a Soviet claim to Bulgaria.{{sfn|Brackman|2001|pp=341–343}}{{sfn|Nekrich|Ulam|Freeze|1997|pp=202–205}} Hitler never responded to Stalin's letter.{{sfn|Donaldson|Nogee|2005|pp=65–66}}{{sfn|Churchill|1949|p=589}} Shortly thereafter, Hitler issued a secret directive on [[Operation Barbarossa|the invasion of the Soviet Union]].{{sfn|Nekrich|Ulam|Freeze|1997|pp=202–205}}{{sfn|Roberts|2006|p=59}} Reasons included the Nazi ideologies of [[Lebensraum]] and [[Heim ins Reich]]<ref>{{Cite book|last=Baranowski|first=Shelley|url=https://books.google.com/books?id=iA-NZ_RgP5kC&q=continental+Lebensraum|title=Nazi Empire: German Colonialism and Imperialism from Bismarck to Hitler|year=2011|publisher=Cambridge University Press|isbn=978-0-521-85739-0}}</ref>