1: The Invasion of Poland by Nazi Germany starts at 4:45 a.m. with the Luftwaffe attacking several targets in Poland. The Luftwaffe launches air attacks against Kraków, Łódź, and Warsaw. By 8:00 a.m., troops of the German Army, still without a formal declaration of war issued, launch an attack near the Polish town of Mokra. 1: Norway and Switzerland declare their neutrality. 1: The British government declares general mobilization of the British Armed Forces and starts evacuation plans in preparation of German air attacks. 2: The United Kingdom and France issue a joint ultimatum to Germany, requiring German troops to evacuate Polish territory; President Douglas Hyde of the Republic of Ireland declares the neutrality of his nation; the Swiss government orders a general mobilization of its forces. 3: At 11:15 a.m. British Standard Time (BST), British Prime Minister Neville Chamberlain announces on BBC Radio that the deadline of the final British ultimatum for the withdrawal of German troops from Poland expired at 11:00am and that "consequently this nation is at war with Germany". Australia, India, and New Zealand also declare war on Germany within hours of Britain's declaration. 3: Bromberg massacre: many ethnic German civilians are killed in the Polish city of Bromberg. 4: In the first British offensive action of the war, the Royal Air Force launch a raid on the German fleet in the Heligoland Bight. South Africa, now under Prime Minister Jan Smuts, declares war on Germany. 6: The German army occupies Kraków in the south of Poland; Polish army is in general retreat. 7: France begins a token offensive, moving into German territory near Saarbrücken. 12: General Gamelin orders a halt to the French advance into Germany. 16: The German Army complete the encirclement of Warsaw. 17: The Imperial Japanese Army launches attacks on the Chinese city of Changsha, when their forces in northern Jiangxi attacked westward toward Henan. Polish submarine escapes from Tallinn; Estonia's neutrality is questioned by the Soviet Union and Germany. 19: The German and Soviet armies link up near Brest Litovsk. 19: The Japanese Imperial Army attacks the Chinese National Revolutionary Army along the Xinqiang River using poison gas during the Battle of Changsha. 20: German submarine U-27 is sunk with depth charges from the British destroyers HMS Fortune and HMS Forester. 24: Soviet air force violates Estonian airspace. 25: German home front measures begin with food rationing. 25: Soviet air activity in Estonia. Soviet troops along the Estonian border include 600 tanks, 600 aircraft and 160 000 men. 28: Soviet troops mass by the Latvian border. 28: Estonia signs a 10-year Mutual Assistance Pact with the Soviet Union, which allows the Soviets to have 30 000-men military bases in Estonia. 30: French forces on the French-German border fall back to the Maginot Line in anticipation of a German invasion.
1: Latvian representatives negotiate with Stalin and Molotov. 3: British forces move to the Belgian border, anticipating a German invasion of the West. 3: Lithuanians meet Stalin and Molotov in Moscow. Stalin offers Lithuania the city of Vilnius (in Poland) in return for allowing Soviet military bases in Lithuania. 5: Latvia signs a 10-year Mutual Assistance Pact with the Soviet Union, which allows the Soviets to have 25,000 men in military bases in Latvia. The Soviets demand military bases. 10: British Prime Minister Chamberlain declines Hitler's offer of peace. 10: Lithuania signs a 15-year Mutual Assistance Pact with the Soviet Union, which allows the Soviets to have 20,000 men in military bases in Lithuania. 11: An estimated 158,000 British troops are now in France. 12: Finland's representatives meet Stalin and Molotov in Moscow. Soviet Union demands Finland give up a military base near Helsinki and exchange some Soviet and Finnish territories to protect Leningrad against Great Britain or the eventual future threat of Germany. 18: First Soviet forces enter Estonia. 3031: As Germany plans for an attack on France, German Lieutenant-General Erich von Manstein proposes that Germany attack through the Ardennes rather than through Belgium - the expected attack route.
1: Soviet Union annexes the eastern parts of occupied Poland to Ukraine and Belorussia. 3: Finland and Soviet Union again negotiate new borders. British bombers coincidentally bomb Munich. 13: Negotiations between Finland and Soviet Union break down. 16: The first British civilian casualty occurs when a German bomber kills James Isbister in an air raid on Orkney in Scotland. 20: The Luftwaffe and German U-boats start mining the Thames estuary. 30: The Soviet Union attacks Finland in what would become known as the Winter War.
1: Russia continues its war against Finland; Helsinki is bombed. 25: The Russian invaders start heavy attacks on the Mannerheim line. A British naval squadron attacks the Admiral Graf Spee. 15: Soviet Army assaults Taipale, Finland during the Battle of Taipale. 18: Germany defeats Britain in the Battle of the Heligoland Bight.
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