<Dl> <Dd> 1: The Republic of China and the Empire of Japan are involved in the early stages of the third year of armed conflict between them during the Second Sino - Japanese War . The war is in what will be known as the "Second Period", which starts in October 1938 and ends in December 1941 . This conflict will eventually be swept up into WWII when Japan joins the Axis and China joins the Allies . </Dd> <Dd> 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 . Within five minutes of the Luftwaffe attacks, Nazi Germany's Kriegsmarine orders the old Battleship Schleswig - Holstein to open fire on the Polish military transit depot at Westerplatte in the Free City of Danzig on the Baltic Sea, but the attack is repulsed . 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 . </Dd> <Dd> 1: Norway and Switzerland declare their neutrality . </Dd> <Dd> 1: The British government declares general mobilization of the British Armed Forces and starts evacuation plans in preparation of German air attacks . </Dd> <Dd> 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 . </Dd> <Dd> 2: The National Service (Armed Forces) Act 1939 is enacted immediately and enforces full conscription on all males between 18 and 41 resident in the UK . </Dd> <Dd> 2: The Free City of Danzig is annexed by Germany . Resistors entrenched in the city's Polish Post Office are overwhelmed . </Dd> <Dd> 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 . </Dd> <Dd> 3: At 12: 30pm BST the French Government delivers a similar final ultimatum; which expires at 3: 00pm BST . </Dd> <Dd> 3: Within hours of the British declaration of War, SS Athenia, a British cruise ship en route from Glasgow, Scotland to Montreal, Quebec, Canada is torpedoed by the German submarine U-30 250 miles (400 km) Northwest of Ireland . 112 passengers and crew members are killed . The "Battle of the Atlantic" starts . </Dd> <Dd> 3: Bromberg massacre: many ethnic German civilians are killed in the Polish city of Bromberg . </Dd> <Dd> 4: At 8: 00 a.m. Newfoundland Standard Time (NST), Dominion of Newfoundland declares war on Germany . </Dd> <Dd> 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 . They target the German pocket - battleship Admiral Scheer anchored off Wilhelmshaven at the western end of the Kiel Canal . Several aircraft are lost in the attack and, although the German vessel is hit three times, all of the bombs fail to explode . </Dd> <Dd> 4: Japan announces its neutrality in the European situation . The British Admiralty announces the beginning of a naval blockade on Germany, one of a range of measures by which the British will wage economic warfare on the Axis powers . </Dd> <Dd> 4: The United States launches the Neutrality Patrol . </Dd> <Dd> 5: South African Prime Minister Barry Hertzog fails to gain support for a declaration of South African neutrality and is deposed by a party caucus for Deputy Prime Minister Jan Smuts . </Dd> <Dd> 5: The United States publicly declares neutrality . </Dd> <Dd> 6: South Africa, now under Prime Minister Jan Smuts, declares war on Germany . </Dd> <Dd> 6: Battle of Barking Creek, a friendly fire incident, results in the first RAF fighter pilot fatality of the War . </Dd> <Dd> 6: The German army occupies Kraków in the south of Poland; Polish army is in general retreat . </Dd> <Dd> 7: France begins a token offensive, moving into German territory near Saarbrücken . </Dd> <Dd> 7: The National Registration Act 1939 is passed in Britain introducing identity cards and allowing the government to control labour . </Dd> <Dd> 8: The British Government announces the re-introduction of the convoy system for merchant ships and a full - scale blockade on German shipping . </Dd> <Dd> 9: The French Saar Offensive stalls at the heavily mined Warndt Forest having advanced approximately 8 miles (13 km) into lightly defended German territory . </Dd> <Dd> 10: After passing both Houses of the Canadian parliament by unanimous consent and receiving Royal Assent by the Governor General of Canada, Lord Tweedsmuir, Canada declares war on Germany on September 10th . </Dd> <Dd> 11: Viceroy of India Lord Linlithgow announces to the two houses of the Indian Legislature (the Council of State and the Legislative Assembly) that due to India's participation in the war, the plans for the Federation of India under the Government of India Act 1935 will be indefinitely postponed . </Dd> <Dd> 12: General Gamelin orders a halt to the French advance into Germany . </Dd> <Dd> 15: The Polish Army is ordered to hold out at the Romanian border until the Allies arrive . </Dd> <Dd> 16: The German Army complete the encirclement of Warsaw . </Dd> <Dd> 16: The French complete their retreat from Germany, ending the Saar Offensive . </Dd> <Dd> 17: The Soviet Union invades Poland from the east, occupying the territory east of the Curzon line as well as Białystok and Eastern Galicia . </Dd> <Dd> 17: Aircraft carrier HMS Courageous is torpedoed and sunk by U-29 on patrol off the coast of Ireland . </Dd> <Dd> 17: The Imperial Japanese Army launches attacks on the Chinese city of Changsha, when their forces in northern Jiangxi attacked westward toward Henan . </Dd> <Dd> 18: Polish President Ignacy Mościcki and Commander - in - Chief Edward Rydz - Śmigły leave Poland for Romania, where they are both interned; Russian forces reach Vilnius and Brest - Litovsk . Polish submarine escapes from Tallinn - Estonia's neutrality is questioned by the Soviet Union and Germany . </Dd> <Dd> 19: The German and Soviet armies link up near Brest Litovsk . </Dd> <Dd> 19: Soviet Union blockades the harbour of Tallinn, the capital of Estonia . </Dd> <Dd> 19: The Japanese Imperial Army attacks the Chinese National Revolutionary Army along the Xinqiang River using poison gas during the Battle of Changsha . </Dd> <Dd> 20: German submarine U-27 is sunk with depth charges from the British destroyers HMS Fortune and HMS Forester . </Dd> <Dd> 21: Romanian Prime Minister Armand Călinescu is assassinated by the Iron Guard, an ultra-nationalistic group in Romania . </Dd> <Dd> 23: The Imperial Japanese Army drive the Chinese National Revolutionary Army out of the Sinchiang river area, and the 6th and 13th Divisions cross the river under artillery cover and advances further south along the Miluo River during the Battle of Changsha . </Dd> <Dd> 24: Soviet air force violates Estonian airspace . The Estonians negotiate with Molotov in Moscow . Molotov warns the Estonians that if the Soviet Union doesn't get military bases in Estonia, it will be forced to use "more radical actions". </Dd> <Dd> 25: German home front measures begin with food rationing . </Dd> <Dd> 25: Soviet air activity in Estonia . Soviet troops along the Estonian border include 600 tanks, 600 aircraft and 160 000 men . </Dd> <Dd> 26: Following a massive artillery bombardment, the Germans launch a major infantry assault on the centre of Warsaw . </Dd> <Dd> 26: Russian bombers seen in the Tallinn sky . </Dd> <Dd> 27: In the first offensive operations by the German Army in Western Europe, guns on the Siegfried Line open up on villages behind French Maginot line . </Dd> <Dd> 28: German - Soviet Boundary and Friendship Treaty is signed by Molotov and Ribbentrop . The secret protocol specifies the details of partition of Poland originally defined in Molotov - Ribbentrop Pact (August 23, 1939) and adds Lithuania to the Soviet Union sphere of interest . </Dd> <Dd> 28: The remaining Polish army and militia in the centre of Warsaw capitulate to the Germans . </Dd> <Dd> 28: Soviet troops mass by the Latvian border . Latvian air space violated . </Dd> <Dd> 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 . As a gift in return Stalin promises to respect Estonian independence . </Dd> <Dd> 29: The Japanese Imperial Army reaches the outskirts of Changsha . However, it is unable to conquer the city because its supply lines are cut off by the Chinese National Revolutionary Army . </Dd> <Dd> 30: The German pocket - battleship Admiral Graf Spee sinks its first merchant ship, the British freighter Clement while off the coast of Pernambuco, Brazil . </Dd> <Dd> 30: French forces on the French - German border fall back to the Maginot Line in anticipation of a German invasion . </Dd> </Dl> <Dd> 1: The Republic of China and the Empire of Japan are involved in the early stages of the third year of armed conflict between them during the Second Sino - Japanese War . The war is in what will be known as the "Second Period", which starts in October 1938 and ends in December 1941 . This conflict will eventually be swept up into WWII when Japan joins the Axis and China joins the Allies . </Dd> <Dd> 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 . Within five minutes of the Luftwaffe attacks, Nazi Germany's Kriegsmarine orders the old Battleship Schleswig - Holstein to open fire on the Polish military transit depot at Westerplatte in the Free City of Danzig on the Baltic Sea, but the attack is repulsed . 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 . </Dd> <Dd> 1: Norway and Switzerland declare their neutrality . </Dd>

What was the first attack in world war 2