World Wars icon
World Wars
Memorial

The dead are not a footnote to the timeline.

World War I and World War II together killed soldiers, civilians, prisoners, deportees, and the persecuted on a scale that reshaped every political map shown above. Any historical interface about these wars should carry memory alongside chronology.

Tens of millions
Approximate combined deaths across both world wars, varying by method of estimation.

Parallel Timelines

Left: World War I. Right: World War II.

WWIWorld War I

1914-1919
1914.06

Sarajevo Assassination

The killing of Archduke Franz Ferdinand triggers the July Crisis.

1914.08

Germany Invades Belgium

Britain enters the war after Belgium's neutrality is violated.

1914.09

First Battle of the Marne

Rapid maneuver warfare gives way to entrenched attrition on the Western Front.

1915.04

Second Ypres

Large-scale poison gas use marks a new level of industrialized killing.

1916.02

Verdun

A symbolic battle of endurance and massive casualties.

1916.07

Somme

Britain launches a major offensive; tanks appear on the battlefield.

1917.04

United States Enters the War

American industry, finance, and manpower alter the long war balance.

1917.11

Russia Exits the Conflict

Revolution reshapes the Eastern Front and German strategy.

1918.11

Armistice

Germany halts fighting; the war ends before the peace settlement begins.

1919.06

Treaty of Versailles

The postwar order is imposed, but its bitterness will outlast the signing.

WWIIWorld War II

1931/1939-1945
1931.09

Mukden Incident

Japanese expansion in Manchuria opens the long Asian crisis.

1937.07

Marco Polo Bridge Incident

Full-scale war begins between China and Japan.

1939.09

Invasion of Poland

Britain and France declare war; Europe enters total conflict.

1940.05

Fall of France

German maneuver warfare breaks Western Europe in weeks.

1940.07

Battle of Britain

Germany fails to secure air supremacy over the United Kingdom.

1941.06

Operation Barbarossa

The Eastern Front becomes the central land war of the century.

1941.12

Pearl Harbor

The United States enters the war; conflict becomes fully global.

1942.06

Midway

Japan loses strategic initiative in the Pacific.

1942.08-1943.02

Stalingrad

German forces are broken in a battle that shifts the Eastern Front.

1944.06

Normandy Landing

A Western front opens in occupied Europe.

1945.05

Germany Surrenders

The European war ends as Berlin falls and the Reich collapses.

1945.08-09

Atomic Bombings and Soviet Entry

Japan faces simultaneous military collapse and unprecedented destruction.

1945.09

Japan Signs the Instrument of Surrender

The second world war formally ends.