The Deadliest Wars in History

Violence between two groups of people has caused more tragedies and loss of human life than anything. Because the number of fatalities caused by wars isn't always clear-cut as methods of counting and accuracy differ, the figures are debated and uncertain. Here are the biggest wars based on casualties including deaths caused by famine, epidemics, and genocide as well as those that are a direct result of fighting.

1. World War II

WWII was a colossal global conflict involving almost every country on the planet. It resulted in the deaths of 70 to 85 million people, more than half of which were civilians. 

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2. Mongol Invasions

The Mongol invasions happened in the 13th and 14th centuries and resulted in the creation of the largest adjoined empire in history. However, this expansion came at the price of 20 to 60 million casualties.

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3. Three Kingdoms

Between the years 220 and 280, three kingdoms dominated China. Infighting between these kingdoms for greater control of the country caused the bloodiest period in Chinese history, leading to 34 million deaths.

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4. Taiping Rebellion

The Taiping Rebellion was a civil war in China from 1850 to 1864 between two ethnic groups, the Hakkas and Manchus. With somewhere between 20 to 30 million casualties, it was the deadliest civil war in all of history. 

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5. World War I

The first World War took place from 1914 to 1918 and was characterized by trench warfare and chemical weapons, resulting in 15 to 30 million fatalities. It was caused by a disturbance in the well-established balance of powers in Europe.

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6. Manchu Conquest of China

This decades-long conflict between the Ming and Qing dynasties in China occurred from 1618 to 1683 and ended with the fall of the Ming dynasty. 25 million people perished in the conflict.

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7. Conquests of Timur

Timur was a 14th century Turco-Mongol conqueror who led military campaigns across Asia, the Caucasus, and Russia. He's considered one of the greatest military rulers in history and also one of the most brutal, causing the deaths of 7 to 20 million people.

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8. An Lushan Rebellion

This Chinese civil war took place between 755 and 763 following a rebel uprising that attempted to overthrow the Tang dynasty. 13 million people died in the conflict which ultimately weakened the Tang dynasty, leading to their eventual demise.

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9. Thirty Years' War

One of the largest conflicts in European history, the Thirty Years' War spanned from 1618 to 1648. It was a religious conflict between Catholic and Protestant states that caused the deaths of four to 12 million people, with parts of Germany losing 50 percent of its population.

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10. Spanish Conquest of Mexico

Between 1519 and 1521, Spanish conquistador Hernán Cortés overthrew one of the most powerful empires in Latin America, the Aztecs. 10 and a half million people died in the conflict which established Spanish dominance in the region.

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11. Spanish Conquest of the Inca Empire

Spain's campaign in Peru was a decades-long conflict with one of the most powerful empires in Western South America, the Incas. The war, which ended with Spanish victory, caused the deaths of 10 million people.

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12. Russian Civil War

One of the key events of the 20th century, the Russian Civil War saw the end of the Russian monarchy with the socialist revolutionary Bolshviks seizing power. Seven to 10 million people died in the conflict which ultimately led to the formation of a communist state.

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13. Chinese Civil War

This decades-long armed conflict was fought between the Republic of China and the Chinese Communist Party from 1927 to 1949. Four to nine million people died in the war which eventually ended in a communist victory.

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14. Crusades

The Crusades were a series of religious wars in the Middle Ages between Christians and Muslims for control over certain areas, namely the Holy Land of Jereusalem. One to nine million died as a result of the crusades which saw mixed outcomes and long-standing religious tensions between the two cultures. 

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15. Reconquista

The Reconquista was a religious war between European Christians and Muslim kingdoms for control of the Iberian peninsula. The conflict spanned over 700 years, killed seven million people, and ended with a Christian victory. 

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16. French Revolutionary and Napoleonic Wars

The French Revolutionary Wars were a series of conflicts between France's Republic and the monarchy. Five to seven million people died in the conflict which ended with the demise of the monarchy, inspiring other European countries to challenge their own traditional royal orders.

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17. Conquests of Menelik II

Menelik II's conquest were a series of wars between 1878 and 1904 aimed at expanding the Ethiopian Empire. The conflict which saw the death of six million people birthed modern Ethiopia but is considered by many historians to constitute genocide.

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18. Second Congo War

One of the largest wars in African history, the Second Congo War began in 1998 with multiple African nations vying for control over the Congo's valuable natural resources. The conflict pulled in nine African countries and caused the deaths of three to five and a half million people. Although technically ended by a peace treaty, the area continues to be plagued by conflict to this day.

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19. Spanish Conquest of New Granada

The Spanish Conquest of New Granada refers to the Spanish takeover of modern-day Colombia and Panama. Over five million people died either in battle or from disease, nearly wiping out the Indigenous population of the area, resulting in a Spanish victory.

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20. Deccan Wars

The Deccan Wars were a series of conflicts in 17th century Indian between the Mughals and local Deccans for control over the Deccan Plateau. Four and a half to five million people died in the conflict which led to a short-lived Mughal victory as they were greatly weakened. 

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