* 1939 – 1945, the Second Battle of the Atlantic.

Subsequent formalizations were framed as attempts to define " effective calculability " or " effective method "; those formalizations included the Gödel – Herbrand – Kleene recursive functions of 1930, 1934 and 1935, Alonzo Church's lambda calculus of 1936, Emil Post's " Formulation 1 " of 1936, and Alan Turing's Turing machines of 1936 – 7 and 1939.

* 1890 – Anthony Fokker, Dutch aviation engineer ( d. 1939 )

* 1939 – André Ouellet, French-Canadian politician

* 1852 – Ferdinand von Lindemann, German mathematician ( d. 1939 )

* 1939 – Alan Ayckbourn, English writer

* 1939 – Johnny Raper, Australian rugby league footballer

* 1939 – The 1939-40 New York World's Fair opens.

* 1939 – NBC inaugurates its regularly scheduled television service in New York City, broadcasting President Franklin D. Roosevelt's N. Y. World's Fair opening day ceremonial address.

* 1939 – First flight of the turbojet-powered Heinkel He 178, the world's first jet aircraft.

* 1939 – William Least Heat-Moon, American author

* 1939 – Edward Patten, American singer-songwriter and producer ( Gladys Knight & the Pips ) ( d. 2005 )

* 1939 – Bulle Ogier, French actress

* 1939 – Romano Prodi, Italian politician and statesman

* 1939 – Hércules Brito Ruas, Brazilian footballer

* 1939 – Albert Einstein and Leó Szilárd write a letter to Franklin D. Roosevelt, urging him to begin the Manhattan Project to develop a nuclear weapon.

* 1939 – Benjamin Barber, American theorist

* 1939 – Wes Craven, American director

* 1939 – John W. Snow, American politician, 73rd United States Secretary of the Treasury

* 1984 – Marvin Gaye, American singer ( The Moonglows ) ( b. 1939 )

* 2001 – Trinh Cong Son, Vietnamese composer ( b. 1939 )

Eastern European theorists include Pyotr Stolypin ( 1862 – 1911 ) and Alexander Chayanov ( 1888 – 1939 ) in Russia ; Adolph Wagner ( 1835 – 1917 ), and Karl Oldenberg in Germany, and Bolesław Limanowski ( 1835 – 1935 ) in Poland.

Relations further deteriorated when, in January 1948, the U. S. State Department also published a collection of documents titled Nazi-Soviet Relations, 1939 – 1941: Documents from the Archives of The German Foreign Office, which contained documents recovered from the Foreign Office of Nazi Germany revealing Soviet conversations with Germany regarding the Molotov-Ribbentrop Pact, including its secret protocol dividing eastern Europe, the 1939 German-Soviet Commercial Agreement, and discussions of the Soviet Union potentially becoming the fourth Axis Power.

Following the downfall of Czechoslovakia and occupation of its Czech part by Nazi Germany in 1939, Czechoslovak units and formations served with the Polish Army ( Czechoslovak Legion ), the French Army, the Royal Air Force, the British Army ( the 1st Czechoslovak Armoured Brigade ), and the Red Army ( I Corps ).

The Holocaust: Nazi Germany | Nazi German extermination and concentration camps in Occupation of Poland ( 1939 – 1945 ) | occupied Poland.

Extermination camps ( or death camps ) were camps built by Nazi Germany during the Second World War ( 1939 – 45 ) to systematically kill millions of people by gassing and extreme work under starvation conditions.

Most Holocaust historians identify six German Nazi extermination camps, all in occupied Poland ; two of them, Chełmno and the Auschwitz II, in the western Polish areas annexed by Nazi Germany ( October 1939 ), four in the General Government area.

* 1939 – Beate Klarsfeld, German Nazi hunter

Finland's foreign politics before this deal had been varied: independence from Imperial Russia with support of Imperial Germany in 1917 ; participation in the Russian Civil War ( without official declaration of war ) alongside the Triple Entente 1918 – 1920 ; a non-ratified alliance with Poland in 1922 ; association with the neutralist and democratic Scandinavian countries in the 1930s ended by the Winter War ( 1939 ); and finally in 1940, a rapprochement with Nazi Germany, the only power able to protect Finland against the expansionist Soviet Union, leading to the Continuation War in 1941.

On 27 September 1939, the security and police agencies of Nazi Germany — with the exception of the Orpo — were consolidated into the Reich Main Security Office ( RSHA ), headed by Heydrich.

The German Nazi invasion of 1939 put an end to it.

Following the German invasion of 1939, Greater Poland was incorporated into Nazi Germany, becoming the province called Reichsgau Posen, later Reichsgau Wartheland ( Warthe being the German name for the Warta river ).

A hagiographic account of Koch's career can be found in the 1939 Nazi propaganda film Robert Koch, der Bekämpfer des Todes ( The fighter against death ), directed by Hans Steinhoff and starring Emil Jannings as Koch.

On August 23, 1939, Germany and the Soviet Union signed the Molotov – Ribbentrop non-aggression pact, which secretly provided for the dismemberment of Poland into Nazi and Soviet-controlled zones.

In August 1939, after Stalin's attempts to establish an Anglo-Franco-Soviet Alliance failed, Stalin entered into a pact with Nazi Germany that divided their influence in Eastern Europe and allowed the USSR to regain some of its lost territories.

After a failed attempt to sign an anti-German military alliance with France and Britain and talks with Germany regarding a potential political deal, on 23 August 1939, the Soviet Union entered into a non-aggression pact with Nazi Germany, negotiated by Soviet foreign minister Vyacheslav Molotov and German foreign minister Joachim von Ribbentrop.

During all this time, Ribbentrop feuded with various other Nazi leaders ; at one point in August 1939 an armed clash took place between supporters of Ribbentrop and those of Propaganda Minister Joseph Goebbels over the control of a radio station in Berlin that was meant to broadcast German propaganda abroad ( Goebbels claimed exclusive control of all propaganda both at home and abroad whereas Ribbentrop asserted a claim to monopolize all German propaganda abroad ).

Ribbentrop, for his part, because of his status as the Nazi British expert, resolved Hitler's dilemma by supporting the anti-British line and by repeatedly advising Hitler that Britain would not go to war for Poland in 1939.

Much of his early work was financed by his family and commerce, but after 1939 he was given resources by the Nazi German government.

The Soldau concentration camp was established in Winter 1939, here 13, 000 people have been murdered by the Nazi German state during the war.

The Treaty of Non-Aggression between Germany and the Soviet Union, also known as the Nazi – Soviet Pact and the Molotov – Ribbentrop Pact ( after its chief architects, Soviet foreign minister Vyacheslav Molotov and German foreign minister Joachim von Ribbentrop ) was a non-aggression pact, signed in Moscow in the late hours of 23 August 1939, at the height of the Nomonhan fighting in the far east between the Soviet Union and the Empire of Japan.

On 31 March 1939, in response to Nazi Germany's defiance of the Munich Agreement and occupation of Czechoslovakia, the United Kingdom pledged the support of itself and France to guarantee the independence of Poland, Belgium, Romania, Greece, and Turkey.

While active collaboration between Nazi Germany and Soviet Union caused great shock in western Europe and amongst communists opposed to Germany, on 1 October 1939, Winston Churchill declared that the Russian armies acted for the safety of Russia against " the Nazi menace.