On April 6, 1917, America would enter World War I, also called the Great War, or “the war to end all wars.” This war between nations would result in the fall of major imperial dynasties (Germany and Austria-Hungary) and lay the groundwork for yet another war two decades later, known as World War II. 

Without the United States’ intervention, Allied Powers – Great Britain, France, Russia, Italy, Romania, and Japan  – wouldn’t have defeated the Central Powers – Germany, Austria-Hungary, Bulgaria, and the Ottoman Empire. 

Although the U.S. vowed to stay neutral, the significant help of their two million troops would tip the scales and defeat the Central Powers.  

What Caused WWI?

The outbreak of World War I can be complex to understand, but we’ll try our best to sum it up in a nutshell. 

Tension had been brewing throughout Europe in the Balkans, an area that includes Greece, for quite some time. Serbian nationalists longed to establish a new power that included Bosnia and Herzegovina; however, they were under Austrian control due to the Balkan Wars that took place some years before. 

In an attempt to support their cause of Serbian nationalism, Serbians assassinated the Austrian archduke, Franz Ferdinand, and his wife while visiting Bosnia on June 28, 1914. 

The chain of events that followed the assassination of Ferdinand escalated quickly, eventually resulting in a war between Europe’s great powers. It didn’t take long for these powers to take sides – Serbia would gain their allies (Russia, Belgium, France, and Great Britain), whereas Austria would gain theirs (Germany). 

WWI Before U.S. Involvement

Each side entered the war on July 28, 1914, with the unrealistic expectation that matters would be resolved within just a few months. However, that was far from true, as the war would cause an incredible amount of damage and last just over four years. 

It began with Germany’s famous military strategy known as the Schlieffen Plan, where Germany would invade two fronts – Belgium in the west and Russia in the east. The plan worked in the west, where German troops would capture the city of Liège and continue to invade until they reached 30 miles from Paris. 

However, French and British forces would make a comeback and successfully drive Germans back into their territory. From here, both sides would dig trenches, where soldiers would stay for more than three years and be subject to numerous ailments such as trench fever and trench foot.

When Did the United States Enter WWI?

Russia’s impatience with the war and their hostility toward Emperor Czar Nicholas II led to the Russian Revolution and their dwindling participation in the war. At this time, France and Great Britain were left to fight the war without very many soldiers. 

Meanwhile, U.S. President Woodrow Wilson had declared neutrality and continued to engage in commerce with both sides. As the war continued, the U.S. found themselves getting involved, as Germany was aggressively attacking U.S. ships on their way to obtain goods. 

It wasn’t until the sinking of the Lusitania in 1915, where Germans killed 1,198 innocent passengers, that America shifted their opinion toward the war. After sinking several more U.S. merchant ships and the Zimmermann Telegram, Woodrow Wilson declared war against Germany and officially entered in on April 6, 1917. 

The U.S. entered just at the right time, increasing Allied troops, blocking German ports, and bringing aviation into the war – an area in which Germany was lacking. 

The End of WWI

Central Powers were being defeated on all fronts, and Austria-Hungary dissolved themselves from the war by reaching a truce with Allied leaders. Germany, being exhausted and outnumbered, surrendered on November 11, 1918, and signed the Treaty of Versailles with the hopes to end all future wars. 

This hefty goal wasn’t achieved, as we know, because two decades later, Germany, who suffered severe reparations, would rise again with resentment, ready to fight in yet another world war in 1939. 

The Aftermath of WWI

World War I resulted in many economic, social, and political consequences. The war took the lives of 16 million soldiers and civilians, which was more than any war before it. Although the U.S. entered the war near the end and didn’t suffer economically, European countries did. 

The war brought about many repercussions, including a severe decline in birth rates since so many young men lost their lives. The population continued to decline even more in 1918, as the war helped to spread one of the world’s deadliest epidemics, the Spanish flu, resulting in 20-50 million more deaths. 

And of course, the Russian Revolution and the Soviet Union joined forces some years later to create a new ideology called Communism, which would be one of the many reasons for entering WWII.

However, not all was bad, as women gained respect from their counterparts since they were forced to enter the workforce to support their families. Upon returning home, men now found it socially acceptable for women to work. 

World War I also brought about many new modern war technologies such as machine guns, tanks, aerial combat, and radio communication. These technological advancements would strengthen the U.S. military significantly. 

More WWI and WWII Resources

World War I is considered to be one of the most celebrated stories in American history. The result of this war not only helped the United States gain military reputation, but also helped them become a trusted ally to many countries. 

It would be nice to say we covered all there is to America’s involvement in World War I, but there’s so much more to unpack, especially World War II (an inevitable consequence of WWI). 

If you’d like to study these wars in more depth, check out our Commemorative 100th Anniversary World War Bundle, which features all of our World War-related products (both WWI and WWII), including our Time Travelers: World War II study. 

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