Japanese soldiers at Marco Polo Bridge.

When Was World War Two?

When was World War Two? This seems like an easy question, but it can be an elusive answer. There are several answers to that question, as many historians debate when World War Two began. The end of World War Two is fairly simple to answer, as the Japanese surrendered on September 2, 1945 in Tokyo Bay.So, when did World War Two begin? Depends on which part of the war you look at.

There are several competing dates for the starting point. If we look at World War Two as a truly global war (which of course it was), and not looking at it from the European or Western point of view, we can pin the answer down to only two dates:

September 18, 1931–The Mukden Incident (also known as the Manchurian Incident) was a pretext for the Japanese invasion and occupation of the region of China known as Manchuria.

July 7, 1937–the Marco Polo Bridge Incident. This is when Japan (one of the Axis powers of World War Two) began its massive invasion of China. 

Many historians prefer the 1937 date over the 1931 incident as the Marco Polo Bridge incident led to a major war between China (which became one of the Allies of World War Two), and Japan and Germany had already, in November of 1936, signed an Anti-Comintern Pact that made them allies against the democracies and against the Soviet Union.

The start of the European part of World War Two is a bit clearer, as most historians put the start date with the German Invasion of Poland on September 1, 1939.

http://www.historyguy.com/wars_of_charlemagne_king_of_franks.htm

Charlemagne Picture by Durer

http://www.historyguy.com/worldwartwo/world_war_two_vocabulary.htm

http://www.historyguy.com/worldwartwo/world_war_two_biographies.htm

http://www.historyguy.com/worldwartwo/naval_war_battle_of_the_atlantic.htm

http://www.historyguy.com/worldwartwo/naval_war_battle_of_the_river_plate.htm

Warsaw Burning During the German Invasion of 1939

 

The German Invasion of Poland (September 1, 1939-October 6, 1939)–Germany invaded Poland on September 1, and Britain, France, and Canada, declared war on Germany on September 3. The Soviet Union joined the war on Germany’s side on September 17, with the Soviet Invasion of Poland from the east. The German Invasion of Poland (called Operation Case White/Unternehmen Fall Weiss by the Germans), marks the beginning of World War Two in Europe.

For more information, links, images, and videos, see:

http://www.historyguy.com/worldwartwo/german_invasion_of_poland_1939.htm

http://www.historyguy.com/worldwartwo/world_war_two_video_german_invasion_of_poland.htm and http://www.historyguy.com/worldwartwo/world_war_two_images_invasion_of_poland.htm

Nazi Germany and the Soviet Union signed a Non-Aggression treaty on August 23, 1939. This treaty between Nazi Germany and the Soviet Union set the stage for the German invasion of Poland a week later, which was the opening round of World War Two in Europe. The second part of this treaty remained secret, and called for the division of Eastern Europe between Hitler and Stalin.

By getting Stalin to agree to not oppose an invasion of Poland, Hitler was assured of a fairly easy war, or so he thought.  The agreement to divide Eastern Europe between them ensured that Moscow would not join the British and French in a defense of Poland.  The Soviet victory four days earlier in the short border war with Japan (See Battle of Khalhkin Gol) allowed Stalin to free up forces for his own aggression against Poland, the Baltic States, and Finland.

Had these two bloody-minded tyrants not signed this treaty, Hitler may not have invaded Poland, thereby triggering the European phase of World War Two.