Alliances and Expansions During World War II

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  • 0:01 World War II Alliances
  • 3:54 World War II Expansions
  • 6:58 Lesson Summary
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Lesson Transcript
Instructor: Nate Sullivan

Nate Sullivan holds a M.A. in History and a M.Ed. He is an adjunct history professor, middle school history teacher, and freelance writer.

In this lesson, we will examine the various alliances and territorial expansions surrounding the Second World War. We will see how these led to the outbreak of war and place them in historical context.

World War II Alliances

Perhaps you've seen or even played the board game Axis and Allies. If so, you're probably familiar with the concept of an alliance. Even if you haven't, I'm sure you understand what an alliance is. The Merriam-Webster Dictionary defines an alliance as 'a group of people, countries, etc., that are joined together in some activity or effort.' Alliances were a major factor in the outbreak of World War I, and they played an important role in World War II as well. Let's look at World War II alliances chronologically.

As fascism and totalitarianism took root throughout the 1930s, countries began falling into camps based on political ideology. Increasingly, the countries of Germany, Italy, and Japan began to realize they had much in common. In 1936, Germany and Japan signed the Anti-Comintern Pact. This pact was basically an anti-communist alliance in which the powers would consult with one another to safeguard common interests.

Fascist Italy joined the Anti-Comintern Pact a year later, setting the foundation for the Rome-Berlin Axis. The Rome-Berlin Axis, or the alliance between Italy and Germany, was cemented under the 'Pact of Steel' in May 1939. The 'Pact of Steel' was officially called 'The Pact of Friendship and Alliance between Germany and Italy.'

Before invading Poland in September 1939, Hitler wanted to make sure the Soviet Union would not come to Poland's aid. To this end, a non-aggression pact was worked out. Formally called the 'Treaty of Non-aggression between Germany and the Union of Soviet Socialist Republics,' the Nazi-Soviet Non-Aggression Pact was signed in late August 1939. The pact is sometimes called the 'Molotov-Ribbentrop Pact,' after the two diplomats who negotiated it. The pact also contained a secret protocol for dividing up Poland into German and Soviet 'spheres of influence.' Basically, this was a plan for both countries to gang up on Poland and divide it between themselves.

In September 1940, Germany, Italy, and Japan agreed to the Tripartite Pact of 1940, formally establishing the Axis Powers. Of course, the countries opposed to the Axis Powers were called the 'Allied Powers,' or just the 'Allies.' Their alliance is sometimes called the 'Grand Alliance.' While different countries entered the war at different times, Great Britain, France, China, the Soviet Union, and the United States are among the most well-known Allied countries.

Remember the Nazi-Soviet Non-Aggression Pact? Well, it was really only a ploy, allowing Hitler to buy time. In the summer of 1941, Nazi Germany launched Operation Barbarossa and invaded the Soviet Union in a surprise attack. In the early stages of the war, even before the United States was officially involved, American aid was supplied to several countries, including Great Britain and the Soviet Union under the Lend-Lease Act.

World War II Expansions

Now, let's take a look at some of the territorial expansions leading up to World War II. Throughout the mid-to-late 1930s, Italy and Japan began invading their respective neighboring states. For example, Italy invaded Ethiopia in 1935 and Albania in 1939. Japan invaded China in 1937 and wreaked havoc upon the capital city of Nanking.

In fact, the term 'Rape of Nanking' describes the atrocities carried out by Japanese soldiers against the Chinese of Nanking city. It is believed roughly 200,000 men were slaughtered and 20,000 women raped. The Japanese also invaded the Soviet Union in 1938. While expansion in Asia was concerning, it was the German expansion that captured the attention of the world.

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