The immediate cause of World War I was the assassination of Archduke Francis Ferdinand and his
wife in Sarajevo, Bosnia, by a Serbian Nationalist protesting against the Austrian annexation of
Bosnia. In the aftermath of the assassinations, Germany supported Austria in a declaration of war
against Serbia. Serbia, a Slavic nation, was in turn linked to Russia’s ethnic policies. By the early
twentieth century, Russia’s policy of Russification , or insistence on the acceptance of Russian culture
by its various ethnic groups, had broadened into a Pan-Slavic movement that was designed to bring
all Slavic nations into a commonwealth with Russia as its head. Russia, therefore, began to mobilize
its troops in defense of Serbia.
Within a few weeks after the assassination at Sarajevo, the system of European alliances had
brought the world into war. Two alliances faced off against each other: the Central Powers of
Germany, Austria-Hungary, the Ottoman Empire, and Bulgaria; and the Allied Powers of Great
Britain, France, Russia, Italy, Japan, and later, the United States. British Commonwealth members
Canada, Australia, and New Zealand took an active part fighting on the Allied side. In 1917, China
also declared war on Germany. Subject peoples of Europe’s colonies in Asia and Africa participated
in the war as combatants and support personnel. Many colonial peoples hoped to be granted
independence as a result of their war efforts.
Throughout the early war years the U.S. government sold arms to the Allies, while U.S. bankers
lent money to the Allied nations. In 1917, the United States was drawn into World War I by two events:
Germany’s declaration of unrestricted submarine warfare and Great Britain’s interception of the
Zimmermann Telegram. The telegram proposed that, if Mexico would enter the war as an ally of
Germany, the German government would assist Mexico to recover the territory it had lost to the
United States as a result of the Mexican War. U.S. entry into World War I provided the Allies with
additional supplies and freshly trained troops, two factors that helped turn the tide of war in favor of
the Allies.
Revolution in Russia
Nationalism and a mutual desire to control Korea led to war between Russia and Japan in 1904. When
the Russo-Japanese War ended in Russian defeat in 1905, an uprising known as the Revolution of
1905 forced Tsar Nicholas II to allow the Duma , or Russian Parliament, to convene. When Nicholas
abolished the Duma a few weeks later, small groups of radicals began planning the overthrow of
tsarist rule.
In March 1917, Russia’s decline as a world power, peasant dissatisfaction, political repression, and
the human and financial costs of World War I brought about the end of tsarist rule. After a weak
provisional government failed to maintain social order, a second revolution in October 1917 brought
the Bolsheviks, or Communists, into power. The new government, led by V. I. Lenin, decided that
Russia was too devastated by revolution to continue the war. In March 1918, Russia and Germany
signed the Treaty of Brest-Litovsk , which ceded vast amounts of Russian territory to Germany.
Between 1918 and 1921, Russia was engaged in a civil war in which the Bolsheviks, or Red Army,
solidified their power over supporters of tsarist rule and wealthy landowners. The opposing forces,
or White Army, were supported by troops from the United States, France, Great Britain, and Japan.
Peace Settlements
Several peace treaties were signed following the war’s end in November 1918; the most well known
was the Treaty of Versailles between most of the Allied nations and Germany. As a result of the