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World History for Kids!

World Wars I and II

In the early 20th century, the countries of Europe had become divided. Tensions were high, and alliances started to form between countries seeking to protect themselves in times of conflict. The result would be the first world war, a war on a scale nobody had never seen before.

Causes of World War I

Under the alliances created before World War I, if any of these countries were to be attacked, their allies agreed to enter the battle to help. But that led to a chain reaction when Archduke Franz Ferdinand of Austria-Hungary was killed by a Serbian man. Austria declared war on Serbia. Serbia’s ally Russia came to their aid. And then Germany, an ally of Austria, decided to declare war on Russia, then declare war on France, another ally of Russia. Germany then invaded Belgium, an ally of France, and Great Britain jumped in to defend the Belgians and French. By the time the war ended, 32 countries were involved, including the United States.

Fighting in World War I

World War I was fought throughout Europe. The two main battlefronts were referred to as the Western Front and the Eastern Front. The Western Front was in western Europe between Switzerland and Belgium, while the Eastern front split Russia from the rest of eastern Europe. The front lines of the battles were fought in trenches, long tunnels dug into the ground to provide cover for the soldiers who were fighting there.

End of World War I

Many thought World War I would only last a few months, but by the end of the war, four years had passed. In the summer of 1918, the Allied forces of Great Britain, France, and the United States launched what would become known as the Hundred Days Offensive. Beginning with the Battle of Amiens in August of 1918, the Allied troops began to advance on German forces, dealing devastating losses for the German military. By the fall of 1918, it had become clear that Germany could not win the war. German leaders officially surrendered on Nov. 11, 1918, ending the war.

Europe After World War I

Europe had been badly damaged by the fighting in World War I. Austria-Hungary dissolved as a country and became four separate countries: Austria, Hungary, Czechoslovakia, and Yugoslavia. Russia gave up land in Europe, which created the countries of Finland, Latvia, Lithuania, and Estonia. The Ottoman Empire kept only Turkey. Even Great Britain, on the winning side of the war, was under economic stress. And Germany dissolved its government at the end of the war.

Buildup to World War II

Japan developed rapidly in the early 20th century, and after World War I, they were left largely unscathed compared to European countries. Japan invaded China in 1937, and its behavior during this conflict upset its former allies.

Meanwhile, in Germany, Adolf Hitler had become chancellor as the head of the Nazi Party. Using propaganda to spread his beliefs, Hitler laid the groundwork to break the treaty that ended World War I and rebuild the German military. On Sept. 1, 1939, Germany invaded Poland, starting World War II in Europe.

Europe During World War II

The fighting in Europe intensified in 1940, when German troops invaded France through the Ardennes Forest. The Germans surprised and overwhelmed the French, and France was defeated quickly. But the Germans suffered great losses in Britain and Russia, and they were forced to surrender in 1945 following the Battle of Berlin.

World War II in the Pacific

On Dec. 7, 1941, Japan attacked the United States naval fleet at Pearl Harbor, Hawaii. Although the attack was intended to keep the American Navy from being a threat, instead, America entered the war. At first, Japanese forces were able to advance quickly, taking many islands in the Pacific. But in 1942, the United States was able to turn the tide, aided by allies including the Chinese. In 1945, the United States was doing well in the Pacific, but the Japanese weren’t backing down, and a new weapon promised to end the war quickly. In August of 1945, President Harry Truman ordered the use of two atomic bombs on the cities of Hiroshima and Nagasaki. The impact of these two bombs was devastating, forcing the Japanese to surrender.