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Assassination of Archduke Franz Ferdinand
The assassination of Austrian Archduke Franz Ferdinand and his wife Sophie in Sarajevo by Gavrilo Princip, a Bosnian Serb nationalist, triggered World War I. Austria-Hungary, with Germany’s support, issued an ultimatum to Serbia, which led to escalated tensions. The event set off a chain reaction of alliances, with major European powers declaring war, resulting in a conflict that would reshape global history. -
Germany Invades Belgium
As part of the Schlieffen Plan, Germany invaded Belgium on August 4, 1914 in an attempt to quickly defeat France before turning east to fight Russia. However, Belgium’s resistance slowed the German advance, and Britain declared war on Germany in response. The invasion demonstrated Germany’s aggressive strategy and led to atrocities against civilians, which fueled Allied propaganda and justified military intervention. -
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Battle of the Marne
The First Battle of the Marne was a crucial Allied victory that halted the German advance into France. French and British forces, using taxis to transport troops to the front, successfully pushed the Germans back, ending hopes for a quick German victory. This battle led to the development of trench warfare on the Western Front, defining the brutal and stagnant nature of World War I. -
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Gallipoli Campaign
The Gallipoli Campaign was a failed Allied attempt to open a supply route to Russia by seizing the Dardanelles Strait. British, Australian, and New Zealand forces landed on the Gallipoli Peninsula but faced fierce Ottoman resistance under Mustafa Kemal. Poor planning and harsh terrain led to heavy casualties, forcing the Allies to withdraw. The campaign boosted Turkish nationalism and shaped the national identities of Australia and New Zealand. -
The Sinking of the Lusitania
A German U-boat torpedoed the British passenger liner Lusitania, killing 1,198 people, including 128 Americans. Germany justified the attack by claiming the ship carried war supplies, but the event sparked international outrage. The sinking increased tensions between Germany and the U.S., influencing American public opinion against Germany and pushing the U.S. closer to entering the war. -
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The Battle of Verdun
One of the longest and bloodiest battles of World War I, Verdun lasted from February to December 1916. The Germans aimed to “bleed France white” by attacking a symbolically important French fortress. French forces, under General Philippe Pétain, defended Verdun at great cost. Over 700,000 casualties resulted, with little territorial gain. The battle exemplified the war’s brutal attrition strategy and the immense human cost of trench warfare. -
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The Battle of the Somme
The Battle of the Somme was one of the deadliest battles in history, with over one million casualties. The British launched the offensive to relieve pressure on the French at Verdun. On the first day, Britain suffered 57,000 casualties, the worst in its history. The battle introduced new military technologies, including the first use of tanks, but ultimately resulted in minimal territorial gain. -
The Zimmerman Telegram
Germany sent the Zimmerman Telegram to Mexico, proposing an alliance in exchange for support against the U.S., promising Mexico the return of Texas, Arizona, and New Mexico. The British intercepted and revealed the message, angering the American public. Combined with unrestricted submarine warfare, the telegram contributed to the U.S. declaring war on Germany in April 1917, marking a turning point in World War I. -
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The Russian Revolution
The Russian Revolution led to the abdication of Tsar Nicholas II, ending centuries of Romanov rule. Discontent over war losses, food shortages, and political repression fueled mass protests. A provisional government was established but struggled to maintain power. In November, the Bolsheviks, led by Lenin, seized control in the October Revolution, withdrawing Russia from World War I and leading to the creation of the Soviet Union. -
The United States Enters the War
The U.S. declared war on Germany, citing unrestricted submarine warfare and the Zimmerman Telegram. American economic and military support provided the Allies with fresh troops and resources, shifting the war’s momentum. The entry of American forces bolstered morale and helped offset German advances, significantly influencing the outcome of World War I. -
Treaty of Brest-Litovsk
The Treaty of Brest-Litovsk ended Russia’s participation in World War I. The Bolshevik government focused on consolidating power, and ceded vast territories to Germany, including Ukraine, Poland, and the Baltic states. This allowed Germany to shift troops to the Western Front, but the treaty became irrelevant after Germany’s defeat later that year. The treaty demonstrated Lenin’s willingness to prioritize revolution over war. -
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The Hundred Days Offensive
From August to November 1918, the Hundred Days Offensive was a series of rapid Allied attacks that pushed German forces back, breaking the stalemate of trench warfare. With American troops arriving in large numbers, the Allies regained momentum. Key battles, including Amiens and Meuse-Argonne, forced Germany into retreat. This offensive directly led to Germany seeking an armistice, effectively ending the war. -
The Armistice
On November 11, 1918, Germany signed an armistice, ending hostilities on the Western Front. The German government, facing internal collapse and military defeat, agreed to harsh terms. Fighting officially ceased at 11:00 AM, marking the end of World War I. The armistice paved the way for the Treaty of Versailles, though many Germans felt betrayed, fostering resentment that contributed to future conflicts. -
The Treaty of Versailles
The Treaty of Versailles officially ended World War I. It imposed heavy reparations on Germany, reduced its military, and redrew European borders. The treaty’s infamous “War Guilt Clause” blamed Germany for the war, fueling resentment. Though it aimed to prevent future conflict, its harsh terms contributed to economic instability and the rise of extremist ideologies, which ultimately led to World War II. -
The League of Nations
The League of Nations was established in 1919 as part of the Treaty of Versailles, aiming to prevent future wars through diplomacy and collective security. Proposed by U.S. President Woodrow Wilson, it lacked U.S. participation due to Senate opposition. While the League had some early successes, its inability to enforce decisions and prevent aggression ultimately rendered it ineffective, setting the stage for global tensions in the 1930s.