World War I (1914-1918)

1914: The Beginning of the War

Major European Powers and Alliances

• Triple Entente: France, Britain, Russia
  • United by fear and suspicion of Germany
• Triple Alliance: Germany, Austria-Hungary, Italy
  • Germany fears encirclement by rivals
  • Italy seeks gains at French expense

The First Spark: Assassination in Sarajevo

• June 28, 1914: Archduke Franz Ferdinand of Austria-Hungary is assassinated by Gavrilo Princip
• Austria-Hungary accuses Serbia of aiding the assassin
• Humiliating ultimatum to Serbia; Serbia rejects it
• Austria-Hungary declares war on Serbia; bombardment of Belgrade

Chain of Mobilizations and War Declarations

• Russia mobilizes to protect Serbia
• Germany mobilizes against Russia and declares war
• Schlieffen Plan: Germany through neutral Belgium for a quick victory over France before Russia mobilizes.
• Germany declares war on France
• Italy and the USA remain neutral
• Britain declares war on Germany after the invasion of Belgium

Beginning of the War

• Six million men march into war across Europe
• British warships win the first naval battle at Heligoland Bight
• More conflicts erupt in Africa, Asia, and the world’s oceans.

1915: Expansion of the Conflict and New Order

Western Front and Trench Warfare

• Britain enforces a naval blockade against Germany
• France initiates Plan XVII: offensive into German territory, but with heavy losses
• Trench warfare begins along the 350-mile front
• Italians launch their first major offensive against Austro-Hungarians

Key Battles

• Battle of the Frontiers: heavy losses for France and Britain
• First and Second Battles of Ypres
  • Germans use poisonous gas for the first time
  • Heavy losses for both sides

Naval and Aerial

• First submarine torpedo attack: HMS Pathfinder
• Introduction of Zeppelins by Germany for bombings

Eastern Front

• German victory at the Battle of Tannenberg and Masurian Lakes
• Russian forces suffer a series of massive defeats

Expansion of the War to the Middle East and Colonies

• Ottoman Empire joins the Central Powers
• Fighting erupts in East Africa, Cameroon, Tanga

1916: Prolonged Warfare and New Strategy

Eastern Front and Austro-Hungarian

• Capture of Przemysl and Italy begins at the Isonzo River
• Verdun becomes one of the most horrific battles of the war
• War for recruitment and the role of women
• Battle of Verdun: 365,000 French casualties, 450,000 German

Western Front

• Battle of the Somme: Worst day for the British Army
  • July 1: 57,000 British casualties in a single day
• British and French offensives

1917: Russian Revolution and America's Entry

Russian Revolution

• Tsar abdicates; Provisional Government takes power
• Russian troops desert en masse

Entry of the United States

• Germany’s unrestricted submarine warfare
• Zimmermann Telegram and U.S. declaration of war
• Bloody April and the French Nivelle Offensive

Collapses, Crises, and Victories

• Battle of Cambrai: first major tank attack
• Armistice signed with Finland
• Bolshevik Revolution; Russian armistice

1918: Final Phase and End of the War

German Offensives and Ally Superiority

• Ludendorff's Spring Offensive: initial success and halt at the Marne River
• American forces enter combat at Cantigny and Belleau Wood
• Final German offensive halted

Allies' Counteroffensive

• Hundred Days Offensive in Amiens: August 8 – 'Black Day' of the German Army
• Bulgaria and Ottoman Empire sign armistice

German Collapse and End of the War

• Armistice of Villa Giusti, Austria’s capitulation, and proclamation of the German Republic
• Armistice of Compiègne and end of the War on November 11, 1918

Consequences and Paris Peace Conference

Treaty of Versailles

• Loss of territory, war reparations, war guilt clause for Germany
• Redrawing of Europe’s borders: emergence of new states
  • Poland, Austria, Hungary, Czechoslovakia, Yugoslavia, an expanded Romania

Casualties and Legacy of the War

• 9.5 million lives lost (soldiers), 7 million civilians
• Destruction of vast areas of Europe and the birth of new states
• New conflicts seeded for the future