13. The Reconquista of Spain took over 700 years and cost the lives of almost 10,000,000 people to accomplish
The Reconquista refers to an extensive series of wars lasting approximately 780 years, starting with the Umayyad conquest of Hispania in 711 and lasting until the fall of the Nasrid kingdom of Granada in 1491. In 711, the Muslim Moors crossed the Strait of Gibraltar to invade the Visigothic Kingdom of Hispania; this conquest would be completed by 719, whereupon the new realm of al-Andalus was created. Struggling to remain independent to the Islamic Umayyad Caliphate based in Córdoba, the Kingdoms of Asturias and Navarre served as the last bastions of Christianity in Spain. Winning several victories, notably the Battle of Toulouse in 721, these small states resisted the total conquest of Spain by the Moors.
With the fall of the Caliphate in the early 11th century, al-Andalus entered a period of prolonged civil war. Splitting into 34 competing kingdoms, the unified Christian kingdoms of the north were free to advance upon them one-by-one. By 1482, only the Emirate of Grenada remained and Ferdinand and Isabella launched the final war. Ending on January 2, 1492, with the surrender of Grenada, the Reconquista was finally completed and Spain turned its eyes towards the New World. At least seven million people were killed across the centuries of conflict, whilst in the aftermath of the Reconquista all Jews were expelled and Muslims were forcibly converted.
12. The Russian Civil War, following on from the losses of the First World War, took the lives of a further 7,000,000 to 12,000,000 people
The Russian Civil War was a multi-factional conflict that chiefly took place between 1917 and 1922 to determine the future of the defunct Russian Empire. Beginning immediately after the Russian Revolutions of 1917, the primary combatants were the Red Army, led by Vladimir Lenin and fighting for the installation of Bolshevism, and the White Army, a broad tent of opposing forces including democrats, monarchists, and capitalists. In addition to these participants, several other independent armies fought for dominance and influence, as well as eight foreign nations which sought to determine the outcome in their respective favors.
With the Red Army ultimately victorious and creating the Soviet Union in 1923, the costs of the internal conflict were staggering. Estimates of the number people executed during the “Red Terror” by the Cheka, the Soviet secret police, ranged from the hundreds of thousands to in excess of one million; concurrently, the “White Terror” is believed to have been responsible for the deaths of 300,000 innocents, including 100,000 Jews in Ukraine. The remnants of the Cossacks were murdered or deported, with approximately half a million estimated to have been put to death. Meanwhile, several independence movements, sensing the weakness of Russian authority, took the occasion to become sovereign nations, including Finland, Estonia, Latvia, Lithuania, and Poland.
11. The Thirty Years’ War, the greatest period of German casualties until the last months of World War II, was responsible for the deaths of between 8,000,000 and 11,500,000 people
The Thirty Years’ War, taking place between 1618 and 1648, was a lengthy conflict fought in Central Europe. Initially beginning due to disagreements between the Protestant and Catholic states of the Holy Roman Empire – accelerated by the election of Ferdinand II as Emperor in 1619 and his efforts to impose Roman Catholicism upon all the peoples of his domain – the war attracted the involvement of the foremost European powers. Seen as an opportunity for expansion and profit, for example, France interceded to prevent encirclement by the Habsburgs, Sweden did so to acquire territory in northern Germany, and Spain in an attempt to crush the Dutch rebellion.
The conflict devastated much of Central Europe, triggering famines, butchering much of the population through the fighting, and bankrupting many of those involved; conversely, France emerged greatly strengthened, as did Sweden, while the Dutch Republic, having won its independence, entered a Golden Age as the foremost economic and colonial power of Europe. Of particular note, due to the sufferings of much of Europe during the conflict many populations adopted the hysterical fear of witchcraft. Serving as the peak of the witch-hunting phenomenon, an estimated 25,000 women were put to death across these decades in a panicked attempt to end the horrific conditions of seemingly cursed everyday life.
10. The Spanish Conquest of the Incas saw the loss of an estimated 8,400,000 native peoples in addition to irreparable damage to the indigenous culture
The Spanish Conquest of the Inca Empire, starting in 1532 and ending in 1572, was one of the fundamental campaigns behind the Spanish colonization of the Americas. Upon the arrival of the Spanish in 1528, the Inca Empire was the largest of the pre-Columbian civilizations, extending across an area approximately 2,000,000 square kilometers in size and encompassing more than 16,000,000 inhabitants. Beginning with the capture of Sapa Inca Atahualpa, the Emperor of the Inca nation, by 180 soldiers under the command of Francisco Pizarro in 1532, the Spanish demanded a substantial ransom for the Inca ruler. After receiving their tribute, the Spanish killed Atahualpa on August 29, 1533.
Despite a protracted rebellion against the Spanish in retaliation, the disunited Inca were unable to provide an adequate military response to the conquistadors. Taking forty years, in part due to an internal Spanish civil war between Pizarro and Diego de Almagro, both of whom were killed in this struggle, the conflict is estimated as having resulted in the deaths of half the indigenous population. Whilst not all in battle, with many dying as a result of smallpox and other diseases brought to the continent by colonists, the Inca civilization was devastated by the defeat and formally replaced by the Viceroyalty of Peru in 1572.
9. In the course of his many conquests, Timur and his armies killed as many as 20,000,000 people
Amir Timur, also known as Tamerlane, was a Turco-Mongol ruler and founder of the Timurid Empire in Central Asia. Born in modern-day Uzbekistan on April 9, 1336, although not a descendant of the Great Khan, Timur envisioned a restoration of the Mongol Empire akin to the greatness of Genghis Khan a century prior. Gaining control of the Chagatai Khanate in 1370, Timur embarked upon successive military campaigns across much of Asia, in addition to Russia and the Caucasus in pursuit of this dream. Defeating the Mamluks of Egypt, the rising Ottoman Empire, and the Sultanate of Dehli, Timur established himself as the preeminent ruler of the Muslim world.
Reuniting much of the composite parts of the Mongol Empire that had splintered following the death of Genghis, including the Chagatai Khanate, the Ilkhanate, and the Golden Horde, Timur came close, but ultimately failed, to restore the final member: the Yuan dynasty of China. In the course of the conflicts, Timur’s armies are estimated to have been responsible for the deaths of approximately 5% of the human population across Asia, Africa, and Europe. However, the Timurid Empire would not long survive its maker. After the death of Timur in 1405 the confederation rapidly declined throughout the 15th century; by 1500, the empire was dissolved and divided up among the Safavids, Mughals, and others.
8. The First World War, the “war to end all wars”, was responsible for the deaths of an estimated 10,000,000 soldiers and laid the groundwork for the resumption of hostilities just two decades later
World War I was a military conflict that engulfed much of the Earth from July 28, 1914, until November 11, 1918, involving more than 70 million soldiers from 32 separate countries. After a period of heightened tensions in Europe, the assassination of the Austro-Hungarian heir, Archduke Franz Ferdinand, in Sarajevo on June 28, 1914, provided the spark to ignite the conflict. After Serbia failed to satisfy Austrian demands in response, war was declared. Two competing alliances of great powers – the Triple Entente consisting of France, Russia, and Great Britain and the Tripple Alliance of Germany, Austro-Hungary, and Italy – mobilized their armies in support of their respective factions and interests.
Although Germany made early advances into France via the Schlieffen Plan, by the end of 1914 the Western Front had stagnated into a stalemate that would continue until 1918. Whilst the Western Front persisted in a condition of perpetual trench warfare, the rest of the world underwent significant turmoil; in February 1917 the Russian Revolution took place, whilst in April 1917 the United States entered the conflict after fearing a German-Mexican alliance. Culminating in the Treaty of Versailles in 1918, the First World War was responsible for the deaths of millions, the disintegration of Russian, German, Austro-Hungarian, and Ottoman Empires, and laid the foundations for the rise of Nazism and the Second World War.
7. The An Lushan Rebellion between the Tang Dynasty and the self-proclaimed Yan Dynasty of China resulted in the deaths of between 13,000,000 and 36,000,000 people
The An Lushan Rebellion was an 8th-century revolt against the Tang dynasty of Imperial China, whereupon in 755 the eponymous favorite general of Emperor Xuanzong proclaimed himself Emperor of the Great Yan dynasty. Seeking to take advantage of the element of surprise, An Lushan’s forces sought to hurriedly consolidate the north and invade the south. Despite superior numbers, the geography of the mountain passes precluded an advance on the capital of Chang’an until 756, at which point Xuanzong was forced to flee to Sichuan where he abdicated his throne.
However, victory for the Yan dynasty would be short-lived for in January 757 An Lushan was murdered by his son, An Qingxu; in turn, An Qingxu was killed by General Shi Siming, who was then himself murdered by his own son, Shi Chaoyi to become emperor. This period of intense instability opened the way for the Tang to regroup and form a united opposition to the rebellion. By the spring of 763 the Yan were defeated and driven from the capital;. After being intercepted escaping, the Yan Emperor committed suicide to avoid capture thus ending the rebellion.
6. As a result of the Spanish Conquest of the Aztec Empire, an estimated 24,000,000 people lost their lives
The Spanish-Aztec War of 1519-1521 was the first conquest by the Spanish Empire of a major pre-Columbian American civilization, setting in motion the European colonization of the Americas. Arriving in Mexico in 1517, two years later an expedition led by Hernán Cortés embarked with the goal of subjugating the native populations. Marching on the city of Cholula, the second largest in Mesoamerica and the center of the Aztec religion, Cortés was welcomed as a guest. Ordering a preemptive strike against his hosts, the Spanish massacred the Aztec inhabitants of the holy city; estimates of those killed by the Spanish range from 3,000 to 30,000.
Marching on the island capital of Tenochtitlan, one of the largest cities in the world with an estimated population of 250,000-300,000 people, the Aztec Emperor, Moctezuma II, welcomed the Spanish to his city. Forced to flee after some of his men attacked and killed much of the Aztec nobility in the “Massacre in the Great Temple”, Cortés would return in 1521 to complete his conquest. Establishing the new capital of Mexico City on the ruins of Tenochtitlan, in 1522 Holy Roman Emperor Charles V proclaimed Cortés captain-general of New Spain as a reward for his services and genocide.
5. The Qing Conquest of the Ming took almost 70 years, costing the Chinese nation more than 25,000,000 lives
The Ming-Qing transition, also known as the Manchu conquest of China, was a sustained period of conflict between the Qing dynasty of Northeastern China and the Ming dynasty of Southern China. Highly unpopular among the peasantry, with the “Seven Grievances” listed against the Ming Emperor, in 1618 the Manchu chieftain Nurhaci began an armed rebellion. Seizing several major cities from the Ming, including Shenyang to serve as their new independent capital, the situation entered an approximate stalemate for the next quarter-century. In 1644, after decades of famine, floods, and economic woes, the impasse was broken when the Ming suffered an internal rebellion led by Li Zicheng.
Capturing Beijing on April 24, 1644, the last Ming Emperor hung himself in the imperial garden and Zicheng proclaimed himself the Shun Emperor. However, in his efforts to solidify his fledgling regime Zicheng sought to purge the military ranks of Ming loyalists. One such general, Wu Sangui, consequently defected to the Qing cause and with their combined forces defeated the new dynasty at the Battle of Shanhai Pass. With no true opposition left, the Qing set about pacifying the remnants of Ming China, a task that would take another forty years to complete. Declaring a new dynasty in 1661, the Kangxi Emperor claimed the throne and, finally, in 1683, after decades of war, the Qing emerged triumphant.
4. The Taiping Rebellion, the largest Chinese conflict since the Qing Conquest, is estimated to have been responsible for the deaths of between 20,000,000 and 70,000,000 people
The Taiping Rebellion was a Chinese civil war that raged from 1850 to 1864, fought between the Qing dynasty and the Taiping Heavenly Kingdom. Based in present-day Nanjing, the Taiping, led by Hong Xiuquan, was a fanatical Christian movement seeking to impose radical social change upon China. Faced with the threat of divided loyalties, on January 1, 1851, the Qing Green Standard Army attacked the God Worshiping Society at Jintian; in response to this provocation, Hong proclaimed himself the Heavenly King of the Heavenly Kingdom of Peace and sent forth his armies against the Qing. Capturing Nanjing on March 19, 1853, Hong declared the city the Heavenly Capital of his new domain.
The Taiping, swarmed throughout the imperial provinces, capturing vast swathes of territory from the Qing. With the Imperial Armies ineffective, the Xian Army, a militia force under Zeng Guofan, served as the primary defense against the dominant Taiping. Following an attempted coup within the Heavenly Empire in 1856, the Xian Army seized the opportunity to reclaim large portions of conquered land. Gaining momentum, the Xian besieged Nanjing in May 1862; despite efforts to break the siege by the superior Taiping numbers, the Qing loyalists held firm. On June 1, 1864, Hong died and Nanjing fell in his absence on July 19. Without central leadership the Heavenly Kingdom fractured, allowing for the gradual defeat of disunited rebellious factions across the next seven years.
3. The Conquests of the Mongol Empire, spanning more than a century, resulted in the deaths of tens of millions in the course of constructing the largest contiguous empire in human history
Beginning in 1206, Genghis Khan, having united the Mongol people under a single banner for the first time in history, unleashed his new empire upon the world. Starting with the invasion of Western Xia, by 1209 the victorious Mongol hordes descended upon their ancient enemy: China. In 1211 the Mongols invaded Jin China, capturing and sacking the capital city of Yanjing. Pivoting to the West after the execution of his ambassadors by the Khwarezmid Empire, Genghis invaded Khwarezmia in 1919; taking just two years to conquer the Central Asian nation, the Mongols slaughtered at least 25% of the local population who suffered approximately 2,000,000 fatalities.
Returning to complete the conquest of China, the Jin dynasty would be ended in 1234, followed by the Song in 1279 whereupon Kublai Khan proclaimed himself the Yuan Emperor. In the interim years, the Mongols, under the leadership of Ögedei Khan, invaded Eastern Europe, defeating Bulgaria, Hungary, Poland, Russia, and Serbia, in addition to solidifying control over the Middle East after the sack of Baghdad in 1258. In total, across more than a century of warfare the Mongols are believed to have been directly responsible for the deaths of 30,000,000 to 40,000,000 people, in addition to displacing hundreds of millions and indirectly causing the calamitous Black Plague in Europe.
2. The Three Kingdoms, during which period China existed in a state of continuous warfare, saw an estimated 40,000,000 lose their lives
The Three Kingdoms was a period of division within mainland China between the competing states of Wei, Shu, and Wu, lasting from 184 to 280. Beginning with the deterioration and eventual collapse of the Han dynasty, and concluding with the ascendance of the Jin, each rival faction claimed dominion over the others as the sole legitimate emperor. Eventually, after decades of war, in 263 the Shu was conquered by the Wei. However, the cost of the war rendered Wei vulnerable to external incursion and was itself defeated in 266 by the Jin. Unable to stand alone against the combined might of the enlarged Jin, Wu was conquered by the Jin in 280 ending the conflict.
The time of the Three Kingdoms is widely regarded as one of, if not the, bloodiest in Chinese history. A census taken in 280 following the reunification of the region under the Jin accounts for 2,459,840 households, encompassing 16,163,863 total subjects. This seemingly large figure was merely a shadow of the population during the preceding Han dynasty, under which 10,677,960 households included at least 56,486,856 individuals – a decline of more than 40,000,000 over the hundred year conflict.
1. World War II, the deadliest war in human history, was responsible for the deaths of as many as 85,000,000 people in just six years
World War II, the largest and deadliest war in human history, was a global total war between 1939 and 1945, involving more than 30 countries and 100 million participants. Traditionally dated as beginning on September 1, 1939, following the invasion of Poland by Nazi Germany and the subsequent declarations of war by the United Kingdom and France in retaliation, the war rapidly expanded to engulf the majority of the world. Spanning multiple theaters of war, including Western and Eastern Europe, North Africa, and the Pacific, the Second World War saw France occupied by Germany in 1940, Japan attack the United States in 1941, and Russia betrayed by Germany only to rally and ultimately capture Berlin in 1945.
Although not even close to the longest war in history, the consequences of World War II were both lasting and devastating. Encompassing the creation and first use of atomic weapons, the mass industrial extermination of humans during the Holocaust, in addition to combat fatalities and widespread starvation, the Second World War is estimated to have been responsible for the deaths of 50,000,000 to 85,000,000. Despite concluding in the unconditional surrender of the Axis to the Allies, tensions did not abate; instead, the emergence of the United States and Soviet Union as rival superpowers merely provided the foundations for the half-century Cold War that was to follow.
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