1. From 1914 to 1919, World War I erupted in Europe
This “Great War” began as a result of competition over imperial territories…
…the build up of powerful, industrial militaries

2. Rivalries due to militarism and imperialism increased nationalism among European powers
British propaganda poster, 1897
Austrian national poster, 1900

3. European rivalries led to two military alliances that threatened to draw European nations into war
England, France, Russia formed the Triple Entente
Austria-Hungary, Italy, Germany formed the Triple Alliance

4. In 1914, Serbian terrorists assassinated Austrian Archduke Franz Ferdinand which triggered the start of World War I
Nowhere was that dispute more likely to occur than on the Balkan Peninsula. This mountainous peninsula in the southeastern corner of Europe was home to an assortment of ethnic groups. With a long history of nationalist uprisings and ethnic clashes, the Balkans was known as the “powder keg” of Europe.
By the early 1900s, the Ottoman Empire, which included the Balkan region, was in rapid decline. While some Balkan groups struggled to free themselves from the Ottoman Turks, others already had succeeded in breaking away from their Turkish rulers. These peoples had formed new nations, including Bulgaria, Greece, Montenegro, Romania, and Serbia.
Nationalism was a powerful force in these countries. Each group longed to extend its borders. Serbia, for example, had a large Slavic population. It hoped to absorb all the Slavs on the Balkan Peninsula. Russia, itself a mostly Slavic nation, supported Serbian nationalism. However, Serbia’s powerful northern neighbor, Austria-Hungary, opposed such an effort. Austria feared that efforts to create a Slavic state would stir rebellion among its Slavic population.
In 1908, Austria annexed, or took over, Bosnia and Herzegovina. These were two Balkan areas with large Slavic populations. Serbian leaders, who had sought to rule these provinces, were outraged. In the years that followed, tensions between Serbia and Austria steadily rose. The Serbs continually vowed to take Bosnia and Herzegovina away from Austria. In response, Austria-Hungary vowed to crush any Serbian effort to undermine its authority in the Balkans
Nationalism was strong in the Balkans, where Serbia hoped to unite with Austrian Slavs

5. Germany and Austria-Hungary were joined by Bulgaria and the Ottoman Empire to form the Central Powers
England, France, and Russia became the Allied Powers and eventually were joined by…

6. …many nations throughout the world, including the United States

7. By 1914, the USA was a world power with overseas territories and influence in Latin America and Asia
But Americans wanted to remain neutral and avoid involvement in Europe’s “Great War”

8. The US felt like it was under attack despite being neutral
Despite efforts by President Woodrow Wilson to remain neutral, the United States joined World War I
The US felt like it was under attack despite being neutral
The sinking of the Lusitania and other examples of German “unrestricted submarine warfare”
The Zimmerman Telegram
Many in the US felt a kinship with Great Britain

9. The USA declared war on the Central Power in April 1917
President Woodrow Wilson promised to “make the world safe for democracy”
The USA declared war on the Central Power in April 1917