Compare and Contrast Physical Maps of Europe

In 1914, some of the most powerful countries of Europe formed rival alliances, with Germany, Austria-Hungary, and Italy in one alliance, and Russia, the U.K., and France in another. 

When Russia and Austria-Hungary intervened in fighting that broke out in the Balkans, the rest of Europe was plunged into World War I, which lasted from 1914-1918.

In the years after World War I, revolution and civil war impacted Russia, Germany, and the remains of Austria-Hungary. 

Europe as a whole was greatly changed as a result.  Russia and Germany became dramatically smaller, and the Russian revolution of 1917 led to the creation of the Soviet Union.  In addition, many smaller states appeared.

World War II began in 1939, when Germany's invasion of Poland forced Britain and France to declare war on Germany.     

By 1942, most of Europe was under the control of Germany and its allies.

But by 1945, the German army was weakened by a reviving Soviet Union, and the war ended in spring of 1945.

Afterward, Germany was much smaller in size and divided into East and West.

And the U.S.S.R. included Estonia, Latvia, Lithuania and Ukraine, and occupied northern East Prussia.

At the end of World War II, many European intellectuals, politicians, and populations as a whole were tired of conflict.

They saw an opportunity to finally create a unified Europe that would not descend into violent conflict again. 

Thus, the idea of a pan-Europe, or United States of Europe, was born. The European Union, or EU, started out as merely a treaty among six nations to trade steel and coal for free with one another. 

After the fall of the Soviet Union in 1991, the geopolitical climate was ready for countries to join a true European Union—a Union with some political capacity—and to unify currencies. 

The EU was established and signed into law in 1992. The Euro came in January 1, 2002. States gave up their own currencies and started using the Euro.