US Imperialism and WW1 – Part 3 of 6 | World War I: Causes and Outbreak

Path to World War I (1871-1914)

Rooted in Franco-Prussian War (1870-71) where Germany's unification humiliated France and disrupted European balance of power.

Alsace-Lorraine

Region France lost to Germany in 1871

Nationalism in Europe

Created unity within nations but rivalry between powers; Slavic nationalism threatened Austria-Hungary.

Imperial Rivalries

Britain

Militarism

Glorification of the military; belief that war was noble; led to massive arms races and readiness for conflict.

Industrialization and War

Modern weapons like machine guns

Arms Race

Competition especially between Britain and Germany over naval dominance (Dreadnought battleships).

Culture of Militarism

Generals and citizens embraced war as a test of national strength and industrial progress.

Alliance System

Pre-war treaties divided Europe into rival blocs for mutual defense.

Triple Alliance

Germany

Triple Entente

France

Effect of Alliances

Local conflicts risked becoming continent-wide wars as allies joined automatically.

Immediate Cause of WWI

Assassination of Archduke Franz Ferdinand of Austria-Hungary on June 28 1914 by Gavrilo Princip

Black Hand

Serbian secret society promoting Pan-Slavism and violence against Austria-Hungary.

German "Blank Check"

July 5 1914 Germany promised unconditional support to Austria-Hungary even against Russia.

Austrian Ultimatum to Serbia

July 23 1914 list of harsh demands; Serbia accepted most but not all.

Outbreak of War Timeline

July 28 Austria-Hungary declared war on Serbia; Russia mobilized; Germany declared war on Russia (Aug 1) and France (Aug 3); invaded Belgium (Aug 4); Britain declared war on Germany; by September all major powers were fighting.

Schlieffen Plan

Germany's plan to defeat France quickly through Belgium before turning east to fight Russia.

Consequences of Alliances

All major powers drawn in—Central Powers (Germany

Conclusion of Causes

Nationalism

Militarism Definition

Policy of building powerful armed forces and using them aggressively to defend or promote national interests.

Militarism Effects

Arms races

Alliances Definition

Formal agreements between nations to provide mutual defense or cooperation.

Alliances Effects

Created entanglements dragging multiple countries into war; increased global scope.

Imperialism Definition

Domination of weaker nations for resources and markets; fueled competition among Great Powers.

Imperialism Effects

Rivalries over colonies and resources; conflict in Africa

Nationalism Definition

Loyalty to one's nation or ethnic group above all else.

Nationalism Effects

Encouraged unity but also conflict; led to ethnic uprisings and desire for independence.

Pan-Slavism

Movement promoting unity of Slavic peoples under Russian leadership; opposed Austro-Hungarian control in Balkans.

Immediate Cause Summary

Assassination triggered alliances to mobilize

July Crisis

Series of escalating declarations and mobilizations from June to August 1914 leading to war.

Industrialization and WWI

Factories

Mass Production

Enabled production of rifles

Mechanization of Warfare

Tanks

Railroads and Telegraphs

Allowed rapid troop and supply movement; made war larger and longer.

Total War

Entire societies and economies mobilized; civilians produced weapons and food for war effort.

Mass Casualties

Industrial weapons created unprecedented death and destruction.

Machine Guns

Fired hundreds of rounds per minute

Heavy Artillery

Long-range cannons caused most casualties; devastated trenches and cities.

Poison Gas

Chlorine

Tanks

First used 1916; could cross trenches but unreliable; early mechanized land warfare.

Airplanes

Began as reconnaissance tools; evolved into fighters and bombers.

Submarines (U-Boats)

German subs targeted Allied shipping; forced convoy systems.

Barbed Wire

Mass-produced obstacle that strengthened defenses.

Communication Tech

Telegraphs

Effect of New Weapons

Created stalemate and trench warfare due to defensive superiority.

Trench Warfare

Dug-in defensive lines stretching 20 000 miles from the English Channel to Switzerland.

Trench Conditions

Mud

Trench Diseases

"Trench foot

No Man's Land

Deadly zone between trenches filled with barbed wire and craters under machine-gun fire.

Trench Warfare Offensives

"Over the top" attacks led to huge losses; little ground gained.

Christmas Truce (1914)

Spontaneous ceasefires where British and German soldiers sang carols

Chemical Warfare

Introduced by France 1914; later used by all sides; psychological weapon with 1.3M casualties and 90-100K deaths.

Tank Warfare

Introduced 1916; aimed to break stalemate but early models often failed.

Air Warfare

Evolved from scouting to air combat and bombing; famous aces included the Red Baron and Eddie Rickenbacker.

War at Sea

Britain blockaded Germany; Germany used unrestricted submarine warfare.

Unrestricted Submarine Warfare (1915)

German U-boats sank enemy and neutral ships without warning—Lusitania (128 Americans) intensified US anger.

Arabic and Sussex Pledges

Germany promised to limit attacks on passenger ships after US protests (1915-1916).

Convoy System (1917)

Allied response grouping merchant ships with naval escorts; reduced U-boat success.

Anti-Submarine Measures

Sonar

WWI Summary 1914-1918

Industrialized global conflict involving alliances