History of War in Timeline

By Popular Timelines Editorial Team · Updated: February 14, 2026

War is defined as an armed conflict involving the armed forces of states. This definition extends to conflicts between governmental forces and organized armed groups capable of sustaining military operations. It also includes conflicts between such organized groups themselves, highlighting the scope of warfare beyond purely interstate conflicts and focusing on the organized and sustained nature of the violence.

1900: Estimates of War Deaths around 1900

Estimates of the percentage of the population killed by wars reached 3% in Europe and "slightly higher" elsewhere between 1400-1900.

1914: Typhus Deaths Exceed Military Action Deaths

From 1500 to 1914, more military personnel were killed by typhus than by military action.

1917: Russian Revolution

Russia's involvement in World War I took such a toll on the Russian economy that it almost collapsed and greatly contributed to the start of the Russian Revolution of 1917.

1939: Start of World War II

World War II, the deadliest war in history, began in 1939.

1940: Increased Production of War Materials

The Great Depression of the 1930s ended as nations increased their production of war materials around 1940.

1941: German Actions in Byelorussian SSR

In 1941, during World War II, German actions on the territory of the Byelorussian SSR led to the deaths of approximately 1.6 million people away from battlefields.

1942: Mental Health Disturbances of American Soldiers

Between 1942 and 1945, one-tenth of mobilized American men were hospitalized for mental disturbances.

1945: Mental Health Disturbances of American Soldiers

Between 1942 and 1945, one-tenth of mobilized American men were hospitalized for mental disturbances.

1945: Increase in Civil Wars

Since 1945, civil wars have increased in absolute terms.

1945: No Battles in Western Europe

Since 1945, no battles have taken place in Western Europe.

1945: Decline in Great Power Wars

Since 1945, there has been a decline in great power wars, territorial conquests, and war declarations.

1945: End of World War II

World War II ended in 1945, causing 70–85 million deaths.

April 1946: Hermann Göring at the Nuremberg trials

Hermann Göring spoke at the Nuremberg trials in April 1946.

1971: Indo-Pakistani War

In 1971, the Indo-Pakistani War took place.

1985: War-related Deaths Estimated Between 1985-1994

It is estimated that between 1985 and 1994, 378,000 people per year died due to war.

1990: War Deaths in 1990

War resulted in 72,000 deaths in 1990.

1991: Estimates of War Deaths Until 1991

For the period 3000 BCE until 1991, estimates of deaths due to war range from 151 million to several billion, with the lowest estimate of 151 million calculated by William Eckhardt.

1992: Publication of "Coercion, Capital, and European States, AD 990–1992"

In 1992, Charles Tilly argued in "Coercion, Capital, and European States, AD 990–1992" that war made the state, and the state made war.

1994: War-related Deaths Estimated Between 1985-1994

It is estimated that between 1985 and 1994, 378,000 people per year died due to war.

1994: Rwandan Genocide Analyzed as Following Youth Bulge

The 1994 Rwandan genocide has been analyzed as following a massive youth bulge.

1996: Publication of "War Before Civilization"

In 1996, Lawrence H. Keeley published "War Before Civilization," arguing that the vast majority of known societies throughout history have engaged in warfare.

2013: War Deaths in 2013

War resulted in 31,000 deaths in 2013.

2023: Estimated War Deaths Until 2023

Data accumulated since Eckhardt's research, especially for the non-European world, was collected, estimating the total for 500 BC - 2023 AD is about 570 million, or 0.95% of people born in the same period.