Prelude to War: The Causes of World War I What were the main causes of World War I? How did the conflict expand to draw in much of Europe? In what ways did the United States respond to the war in Europe?
Voices from the Past….
“The world must be made safe for democracy.” Woodrow Wilson “We are a composite and cosmopolitan people. We are of the blood of all the nations that are at war.” Wilson’s 2nd Inaugural
“We intend to begin unrestricted submarine warfare…We shall endeavor in spite of this to keep the U.S. neutral. In the event of this not succeeding, we make Mexico a proposal of alliance…” Arthur Zimmerman, 1917 German Foreign Secretary
“Hospital trains brought them filthy, hungry, exhausted to us. Many of them had their faces blown away; pus flowed down their chests… Hideous mutilation was the rule, not the exception.” WW I Nurse Katrina Herzer
“We desire neither conquest nor advantage. We wish nothing that can be had only at the cost of another people. We always professed unselfish purpose and we covet the opportunity to prove our professions are sincere…” Wilson’s 2nd Inaugural
Long Term Causes‌. Imperialism
Competition for colonial lands in Africa and elsewhere led to conflict among the major European powers.
Militarism
By the early 1900s, powerful nations in Europe had adopted policies of militarism, or aggressively building up armed forces and giving the military more authority over government and foreign policy.
Nationalism
One type of nationalism inspired the great powers of Europe to act in their own interests. Another emerged as ethnic minorities within larger nations sought selfgovernment.
Alliances
In a complicated system of alliances, different groups of European nations had pledged to come to one another’s aid in the event of attack.
The Spark! Immediate cause!  The immediate cause of the Great War, later to be known as World War I, was the assassination of Archduke Francis Ferdinand in Sarajevo, Bosnia, on June 28, 1914. However, the main causes of the war existed long before 1914.  At the time of his assassination, Francis Ferdinand, heir to the throne of the Austro-Hungarian Empire, had been visiting Bosnia, a new Austro-Hungarian province. He was shot by Gavrilo Princip, a 19-year-old Bosnian nationalist who believed that Austria-Hungary had no right to rule Bosnia.
The Conflict spreads…. Convinced that Serbia was behind the Archduke’s assassination, AustriaHungary declared war on Serbia on July 28, 1914. Russia, as Serbia’s protector, began mobilization, or the readying of troops for war. France, Russia’s ally, and Germany, Austria-Hungary’s ally, also began mobilization. Germany, located between France and Russia, wanted to conquer France quickly to avoid the need to fight on two fronts. To get to France, German forces had to pass through neutral Belgium; the invasion of Belgium brought Britain into the conflict as well. One week after the war started, all the great powers of Europe had been drawn into it. Germany and Austria-Hungary formed the Central Powers, while Russia, France, Serbia, and Great Britain were called the Allies.
War in Europe! When Austria-Hungary declared war on Serbia, the complex alliance system in Europe drew much of the continent into the conflict.
Alliances
Stalemate in Europe…. By September 1914, the war had reached a stalemate, a situation in which neither side is able to gain an advantage. When a French and British force stopped a German advance near Paris, both sides holed up in trenches separated by an empty “no man’s land.” Small gains in land resulted in huge numbers of human casualties. Both sides continued to add new allies, hoping to gain an advantage.
Modern War!  Neither soldiers nor officers were prepared for the new, highly efficient killing machines used in World War I.  Machine guns, hand grenades, artillery shells, and poison gas killed thousands of soldiers who left their trenches to attack the enemy.  As morale fell, the lines between soldiers and civilians began to blur. The armies began to burn fields, kill livestock, and poison wells.
The American Response Because many Americans were European immigrants or the children of European immigrants, many felt personally involved in the escalating war. Although some had sympathies for the Central Powers, most Americans supported the Allies. Support for the Allies was partially caused by Germany’s rule by an autocrat, a ruler with unlimited power. In addition, antiGerman propaganda, or information intended to sway public opinion, turned many Americans against the Central Powers. To protect American investments overseas , President Wilson officially proclaimed the United States a neutral country on August 4, 1914.
Quick Quiz‌. Which of the following was a cause of World War I? (A) (B) (C) (D)
Rising nationalism in European nations Decrease in militarism among European powers Pro-German propaganda in Britain United States support of the Central Powers
Why did the United States proclaim its neutrality in August 1914? (A) (B) (C) (D)
To please supporters of both sides To protect its overseas investments To allow time for preparedness To aid Great Britain
America moves toward war... How did Germany’s use of submarines affect the war? What moves did the United States take toward war in early 1917?
Germans use the U-boat…. To break a stalemate at sea, Germany began to employ U-boats, short for Unterseeboot, the German word for submarine. U-boats, traveling under water, could sink British supply ships with no warning. When the British cut the transatlantic cable, which connected Germany and the United States, only news with a pro-Allied bias was able to reach America. American public opinion was therefore swayed against Germany’s U-boat tactics
.
The Lusitania! The Sinking of the Lusitania  On May 7,1915, a German U-boat sank the British passenger liner Lusitania, which had been carrying both passengers and weapons for the Allies.  Since 128 American passengers had been on board, the sinking of the Lusitania brought the United States closer to involvement in the war.
Sussex Pledge & Unrestricted Submarine Warfare The Sussex Pledge More Americans were killed when Germany sank the Sussex, a French passenger steamship, on March 24,1916. In what came to be known as the Sussex pledge, the German government promised that U-boats would warn ships before attacking, a promise it had made and broken before. Unrestricted Submarine Warfare On January 31, 1917, Germany announced its intent to end the Sussex pledge and return to unrestricted submarine warfare. This action caused the United States to break off diplomatic relations with Germany. Despite this announcement, the German navy did not attack any American ships in February, causing the United States to continue to hope for peace.
Zimmermann Note! The Zimmermann Note During this time, Britain revealed an intercepted telegram to the government of Mexico from Germany’s foreign minister, Arthur Zimmermann. In this telegram, known as the Zimmermann note, Germany offered to return American lands to Mexico if Mexico declared war on the United States. Neither Mexico nor President Wilson took the Zimmermann note seriously, but it brought America closer to entering the war.
Tensions Increase…. Wilson’s war message
As Germany continued to sink American ships in March, President Wilson’s patience for neutrality wore out. On April 6, 1917, the President signed Congress’s war resolution, officially bringing the United States into the war.
President Woodrow Wilson
Quick Quiz‌. What was the significance of the Lusitania? (A) (B) (C) (D)
Its sinking brought America closer to entering the war. The weapons it carried helped Britain gain an advantage. Its crew delivered the Zimmermann note. It inspired the Sussex pledge.
Why did the Russian Revolution help bring America into the war? (A) (B) (C) (D)
It helped the German navy sink British ships. It caused the deaths of many Americans. It set up a republican government in Russia, an Allied nation. It promised American lands to Mexico in exchange for an invasion.