WWII Overview

I treat WWII as two wars in two different geographic areas:

Our War with Japan, with the United State's primary allies being The Republic of China and the British Empire. This war began in December 1941 with Japanese attacks on Pearl Harbor and elsewhere in east Asia and the Pacific. Combat ended in August 1945 after the US use of two atomic bombs on the Japanese homeland and the Soviet Union's declaration of war on the Japanese Empire. The Japanese war was fought throughout much of eastern and southeastern Asia and the western and central Pacific.
Our War with Germany, with the United State's primary allies being the British Empire and the Soviet Union. Germany began this war by invading Poland in September 1939, achieved an astonishing victory in France in 1940, and expanded the war by an order of magnitude with an invasion of the Soviet Union in June 1941. US active involvement began in December 1941 and ended in May 1945 with the collapse of the German government and German military resistance. The German component of World War II was fought throughout most of Europe and North Africa.

Japanese Proposed Division of Eurasia, 15 Dec 1941

As the above map shows, the War with Japan and the War with Germany were quite separate geographically. The four thick arrows show planned offensives that would have brought Japanese and German forces together, but fortunately never happened.

The red and orange areas represent the Axis powers, their allies, and the territory they occupied as of September 1942.

The United States was already drifting towards war with both Japan and Germany when the Japanese Empire launched its fateful surprise attacks on December 7, 1941. (December 8 west of the International Date Line.)

Japan - the United States had imposed economic sanctions attempting to curtail Japan's brutal aggression in China and expansionist tendencies in the southeast Asia area.
Germany - the United States was taking increasingly bold actions in the North Atlantic to maintain the maritime supply line to Great Britain.

Some comments on my World War II modules scope and perspective:

Big Pigeon's WWII - Japan and WWII - Germany modules focus on United States involvement in WWII. Even though only about 1% of those who died worldwide because of WWII were American, I emphasize the American experience.
My goal - To remember the men and women of the Pottawattamie area in southwestern Iowa who served in WWII but did not survive.
Thus, each of my WWII - Japan and WWII - Germany modules contain about fifty webpages which summarize a battle or campaign followed by a list of those from the Pottawattamie area who died during that event.

The names of countries:
You may see different names than those I use for some of the countries that fought in World War II:

Russia - Union of Soviet Socialist Republics abbreviated as USSR, the Soviet Union
China - Republic of China
Japan - Japanese Empire
Germany - the Third Reich
England - Great Britain

About commonwealths and empires during WWlI:

The major countries in the British Commonwealth of independent nations were Canada, South Africa, Australia and New Zealand.
The Philippine Islands were a US commonwealth scheduled for independence in 1946.
England, France, the Netherlands, Japan and Italy were colonial powers whose colonies figured prominently in the war.
The major British colony was India, which consisted of today's countries of India, Pakistan, and Bangladesh.
Since the British Empire and Commonwealths were major contributors to the Allied armed forces, I will often use British Empire instead of British or Great Britain in my text.

Notes:

Our major WWII enemies, collectively referred to as the Axis, consisted of Germany, Japan and Italy. However, they were supported by a number of smaller nations, ranging from Vichy France in western Europe to Siam (now Thailand) in Southeast Asia. Italy left the Axis early, in the summer of 1943. I focus on the major powers whom the US fought, namely Japan and Germany.
Throughout my WWII-Japan and WWII-Germany modules, I use maps to support my text. You can usually enlarge a map or photo by clicking on it.

Sources for the WWII > WWII Overview webpage:

The Proposed Division of Eurasia map, https://en.wikipedia.org/wiki/Axis_powers_negotiations_on_the_division_of_Asia.