Waging war has been the main occupation of man since the first recorded civilizations.
According to the Oxford English Dictionary, “war” is defined as
- A state of armed conflict between different countries or different groups within a country.
- A state of competition or hostility between different people or groups.
- A sustained campaign against an undesirable situation or activity.
The deadliest war in history, in terms of the cumulative number of deaths since its start, is World War II, from 1939 to 1945, followed by the Mongol conquests at up to 50 million. Three of the ten most costly wars, in terms of loss of life, have been waged in the last century. These are the two World Wars, followed by the Second Sino-Japanese War (which is sometimes considered part of World War II, or as overlapping). Most of the others involved China or neighboring peoples.
World War II cost the most human life, fatalities numbering 56.4 million including civilians. Poland lost 6 million (17% of their population). Four out of five Russian men born in 1923 were killed in World War II.
August 6, 1945 the US dropped and atomic bomb on Hiroshima killing over 130,000. Another 25,200 died from radiation within the next year. Approximately 83,000 people were killed in Tokyo, Japan on March 10, 1945.
The Battle of Somme, France claimed 1.22 million casualties (dead and wounded). The highest death toll of 1.1 million in the Battle of Stalingrad. Of this total, only 1,515 civilians of an original 500,000 survived.
As far as civil wars are concerned, the Taiping Rebellion that occurred between 1851 and 1864 against the Qing dynasty in China was responsible for 20 million deaths.
Killers and fanatics are more modest contributors. An Indian Thug named Behram strangled at least 931 victims in the Oudh district from 1790 to 1840. Possibly as many as 2 million Indians were strangled by the Thuggee cult between 1550 and 1853.
Why Do Wars Happen?
Wars have been a part of human history for thousands of years, and have become increasingly destructive as industrialization and technology have advanced.
There is rarely one single, clear cause of conflict and, ultimately, war. The causes of a war are usually numerous and can often be intertwined in a complicated way.
Many theories have been put forth over the years as to why wars happen, and some of the greatest minds have offered their take on the subject.
Eight Main Causes of War
- Economic Gain
- Territorial Gain
- Religion
- Nationalism
- Revenge
- Civil War
- Revolutionary War
- Defensive War
According to Carl von Clausewitz, war is nothing but a duel on an extensive scale…’ an act of violence intended to compel our opponent to fulfill our will,’ directed by political motives and morality. (Clausewitz 1940: Book I, Ch. I).
Clausewitz acknowledged the link between war and politics, ‘War is nothing more than the continuation of politics by other means… For political aims are the end and war is the means, and the means can never be conceived without the end.’ The greater the motives for war, the more the existence of the entire nation is concerned, and the more violent the tension will be which precedes the war.
War is neither a scientific game nor an international sport; it is an act of violence, characterized by destruction. According to Clausewitz, war is always limited by ‘friction’ – uncertainty, chance, and inevitable logistical or organizational misfortunes. Also mentioned is the notion of ‘rational calculus,’ that states intrinsically use violence to achieve a desired end. The less controlled the use of violence is by one side, the lengthier the war.
List of major wars
Ancient wars (Before 500 AD)
| War | Death range | Date | Combatants | Location |
|---|---|---|---|---|
| Conquests of Cyrus the Great | 100,000+ | 549 BC–530 BC | Persian Empire vs. various states | Middle East |
| Greco–Persian Wars | 300,000+ | 499 BC–449 BC | Greek City-States vs. Persian Empire | Greece |
| Samnite Wars | 33,500+ | 343 BC–290 BC | Roman Republic vs. Samnites | Italy |
| Wars of Alexander the Great | 142,000+ | 336 BC–323 BC | Macedonian Empire and other Greek City-States vs. various states | Middle East / North Africa / Central Asia / India |
| Punic Wars | 1,250,000–1,850,000 | 264 BC–146 BC | Roman Republic vs. Carthaginian Empire | Western Europe / North Africa |
| First Punic War | 400,000+ | 264 BC–241 BC | Roman Republic vs. Carthaginian Empire | Southern Europe / North Africa |
| Second Punic War | 770,000+ | 218 BC–201 BC | Roman Republic vs. Carthaginian Empire | Western Europe / North Africa |
| Third Punic War | 150,000–250,000 | 149 BC–146 BC | Roman Republic vs. Carthaginian Empire | Tunisia |
| Kalinga War | 150,000–200,000 | 262 BC–261 BC | Maurya Empire vs. State of Kalinga | India |
| Qin’s Wars of Unification | 700,000+ | 230 BC–221 BC | Qin state vs. Han, Zhao, Yan, Wei, Chu, Qi States | China |
| Cimbrian War | 410,000–650,000 | 113 BC–101 BC | Roman Republic vs. Cimbri and Teutones | Western Europe |
| Gallic Wars | 1,000,000+ | 58 BC–50 BC | Roman Republic vs. Gallic tribes | France |
| Iceni Revolt | 150,000+ | 60–61 | Roman Empire vs. Celtic tribes | England |
| Jewish–Roman Wars | 1,270,000–2,000,000 | 66–136 | Roman Empire vs. Jews | Middle East/North Africa |
| First Jewish–Roman War | 250,000–1,100,000 | 66–73 | Roman Empire vs. Jews | Middle East |
| Kitos War | 440,000+ | 115–117 | Roman Empire vs. Jews | Southern Europe / North Africa |
| Bar Kokhba Revolt | 580,000 | 132–136 | Roman Empire vs. Jews | Middle East |
| Gothic War (269) | 320,000+ | 269 | Roman Empire vs. Goths | Europe |
| Probus’s German War | 400,000+ | 277 | Roman Empire vs. Germans | Europe |
| Gothic War (376–382) | 40,000+ | 376–382 | Roman Empire vs. Goths | Eastern Europe |
| Three Kingdoms War | 36,000,000–40,000,000 | 184–280 | Wei vs. Shu vs. Wu | China |
| Yellow Turban Rebellion | 3,000,000–7,000,000 | 184–205 | Peasants vs. Eastern Han China | China |
| Wars of the Sixteen Kingdoms | 150,000+ | 304–439 | Northern Chinese States | Northern China |
| Hunnic Reclaims | 165,000+ | 395–453 | Roman Empire vs. Hunnic Empire | Europe |
Medieval wars (500–1500 AD)
| War | Death range | Date | Combatants | Location |
|---|---|---|---|---|
| Arab–Byzantine Wars | 2,000,000+ | 629–1050 | Byzantine Empire and allies vs. Islamic Empire and Allies | Middle East / North Africa / Southern Europe |
| Reconquista | 7,000,000-10,000,000 | 711–1492 | Spanish and Portuguese states vs. Muslim states | Iberian Peninsula |
| Goguryeo–Sui War | 300,000+ | 598–614 | Sui Dynasty China and Goguryeo Kingdom | China, Korea |
| An Lushan Rebellion | 13,000,000–36,000,000 | 755–763 | Tang Dynasty China and Islamic Empire vs. Yan state | China |
| Goryeo–Khitan Wars | 90,000+ | 993–1019 | Liao Empire vs. Goryeo Kingdom | Korea |
| Song–Đại Việt war | 600,000+ | 1075–1077 | Song Empire vs. Dai Viet Kingdom under Lý dynasty | China, Vietnam |
| Crusades | 1,000,000–3,000,000 | 1095–1291 | Originally Byzantine Empire vs. Seljuq Empire, but evolved into Christians vs. Muslims. | Europe / Middle East (“Holy Land”) |
| Albigensian Crusade | 200,000–1,000,000 | 1208–1229 | Papal States and France vs. Cathartic States | France |
| Mongol invasions and conquests | 30,000,000–40,000,000 | 1206–1368 | Mongol Empire vs. Several Eurasian states | Eurasia |
| Wars of Scottish Independence | 60,000–150,000 | 1296–1357 | Scotland vs. England | Scotland / England |
| Hundred Years’ War | 2,300,000–3,300,000 | 1337–1453 | House of Valois vs. House of Plantagenet | Western Europe |
| Conquests of Timur | 8,000,000–20,000,000 | 1370–1405 | Timurid Empire vs. several middle eastern states | Eurasia |
| Wars of the Roses | 35,000–105,000 | 1455–1487 | House of Lancaster, House of Tudor, and allies vs. House of York and allies | England / Wales |
Pre modern (1500 AD–2000) wars with greater than 25,000 deaths
| War | Death range | Date | Combatants | Location |
|---|---|---|---|---|
| Italian Wars | 300,000–400,000 | 1494–1559 | Holy Roman Empire, Spain, and some Italian States vs. France, Ottoman Empire, and some Italian states | Southern Europe |
| Spanish conquest of the Aztec Empire | 2,300,000+ | 1519–1632 | Spanish Colonial Empire vs. Aztec Empire | Mexico |
| Spanish conquest of Yucatán | 1,460,000+ | 1519–1595 | Spanish Colonial Empire vs. Mayan States | North America |
| Spanish conquest of the Inca Empire | 8,400,000+ | 1533–1572 | Spanish Colonial Empire vs. Inca Empire | Peru |
| Campaigns of Suleiman the Magnificent | 200,000+ | 1521–1566 | Ottoman Empire vs. several Balkan, African, and Arabian States | Eastern Europe / Middle East / North Africa |
| German Peasants’ War | 100,000+ | 1524–1525 | German Peasants vs. Swabian League | Germany |
| French Wars of Religion | 2,000,000–4,000,000 | 1562–1598 | Protestants vs. France vs. Catholics | France |
| Eighty Years’ War | 600,000–700,000 | 1568–1648 | Dutch Republic, England, Scotland, and France vs. Spanish Empire | Worldwide |
| Anglo-Spanish War (1585–1604) | 138,285+ | 1585–1604 | Spanish Empire and allies vs. Kingdom of England and allies | Europe / Americas |
| Japanese invasions of Korea | 1,000,000+ | 1592–1598 | Kingdom of Great Joseon and Ming China vs. Japan | Korea |
| Nine Years’ War (Ireland) | 130,000+ | 1593–1603 | Irish rebels vs Kingdom of England | Ireland |
| Transition from Ming to Qing | 25,000,000+ | 1616–1683 | Qing China vs. Ming China vs. Shun dynasty China (Li Zicheng) vs. Xi dynasty China (Zhang Xianzhong vs. Kingdom of Shu (She-An Rebellion) vs. Evenk-Daur federation (Bombogor) | China |
| Thirty Years’ War | 4,000,000–12,000,000 | 1618–1648 | Pro-Habsburg states vs. Anti-Habsburg states | Europe |
| Franco-Spanish War (1635–1659) | 200,000+ | 1635–1659 | France and Allies vs. Spain and Allies | Western Europe |
| Wars of the Three Kingdoms | 876,000+ | 1639–1651 | Royalists vs. Covenanters vs.Union of the Irish vs. Scottish Protestants vs. Parliamentarians | British Isles |
| English Civil War | 211,830+ | 1642–1651 | Royalists vs. Parliamentarians | England, Scotland, and Ireland |
| Deluge | 3,000,000 | 1655–1660 | Primarily Poland vs. Sweden and Russia | Poland |
| Mughal–Maratha Wars | 5,000,000+ | 1658–1707 | Maratha empire vs. Mughal Empire | India-Bangladesh |
| Franco-Dutch War | 342,000 | 1672–1678 | France and allies vs. Dutch Republic and allies | Western Europe |
| Great Turkish War | 380,000+ | 1683–1699 | Ottoman Empire vs. European Holy League | Eastern Europe |
| Nine Years’ War | 680,000+ | 1688–1697 | France vs. League of Augsburg (Dutch, Habsburgs, England, Scotland, Spain and others) | Global (mainly Europe) |
| Great Northern War | 350,000+ | 1700–1721 | Russia and allies vs. Swedish Empire | Eastern Europe |
| War of the Spanish Succession | 400,000–1,250,000 | 1701–1714 | Grand Alliance vs. Bourbon Alliance | Europe / Americas |
| Maratha expeditions in Bengal | 400,000+ | 1741–1751 | Maratha Empire vs. Nawab of Bengal | India, Bangladesh |
| Seven Years’ War | 868,000–1,400,000 | 1756–1763 | Great Britain and allies vs. France and Allies | Worldwide |
| Sino-Burmese War | 70,000+ | 1765–1769 | Burma vs. Qing China | Southeast Asia |
| Tây Sơn rebellion | 1,200,000–2,000,000+ | 1771–1802 | Tây Sơn rebels then dynasty (British supports) and Chinese pirates vs Nguyễn lords, Trịnh lords, Lê dynasty of Vietnam; Siam; Qing dynasty of China; Kingdom of Vientiane; French army. | Southeast Asia |
| American Revolutionary War | 70,000-116,000 | 1775–1783 | United States and allies vs. British Empire and German Mercenaries | Worldwide |
| White Lotus Rebellion | 100,000+ | 1794–1804 | Qing China vs. White Lotus rebels | China |
| French campaign in Egypt and Syria | 65,000+ | 1798–1801 | France vs. Ottoman Empire and Great Britain | Middle East / North Africa |
| Saint-Domingue expedition | 135,000+ | 1802–1803 | France vs. Haiti and UK | Haiti |
| Napoleonic Wars | 3,500,000–7,000,000 | 1803–1815 | Coalition powers vs. French empire and allies | Worldwide |
| French invasion of Russia | 540,000+ | 1812 | French Empire vs. Russia | Russia |
| Spanish American wars of independence | 600,000+ | 1808–1833 | Spain and Portugal vs. American Independentists | Americas |
| Venezuelan War of Independence | 228,000+ | 1810–1823 | Spain vs. Venezuelan states | Venezuela |
| Mfecane | 1,000,000–2,000,000 | 1810s–1840s | Ethnic communities in southern Africa | Modern day South Africa |
| Carlist Wars | 200,000+ | 1820–1876 | Carlist Insurgents vs. Spain | Spain |
| Greek War of Independence | 170,000+ | 1821–1831 | Greek Revolutionaries vs. Ottoman Empire | Greece |
| French conquest of Algeria | 480,000–1,000,000 | 1830–1903 | France vs. Algerian resistance | Algeria |
| Taiping Rebellion | 20,000,000–70,000,000 | 1850–1864 | Qing China vs. Taiping Heavenly Kingdom | China |
| Crimean War | 356,000–615,000 | 1853–1856 | Ottoman Empire and allies vs. Russia | Crimean Peninsula |
| Red Turban Rebellion (1854–1856) | 1,000,000+ | 1854–1856 | Qing China vs. Red Turban rebels | China |
| Miao Rebellion | 4,500,000 | 1854–1873 | Qing China vs. Miao | China |
| Punti–Hakka Clan Wars | 500,000–1,000,000+ | 1855-1868 | Hakka vs. Punti | China |
| Panthay Rebellion | 890,000–1,000,000 | 1856–1873 | Qing China vs. Hui | China |
| Indian Rebellion of 1857 | 800,000–1,000,000 | 1857–1858 | Sepoy Mutineers vs. British East India Company | India |
| American Civil War | 650,000–1,000,000 | 1861–1865 | Union States vs. Confederate States | USA |
| Dungan Revolt | 8,000,000–20,000,000 | 1862–1877 | Qing China vs. Hui vs. Kashgaria | China |
| French intervention in Mexico | 49,287+ | 1862–1867 | Mexican Republicans vs. France and Mexican Empire | Mexico |
| Paraguayan War | 300,000–1,200,000 | 1864–1870 | Triple alliance vs. Paraguay | South America |
| Austro-Prussian War | 40,000+ | 1866 | Austrian states vs. German states | Central Europe |
| Ten Years’ War | 241,000+ | 1868–1878 | Spain vs. Cuba | Cuba |
| Franco-Prussian War | 433,571+ | 1870–1871 | France vs. German states | France and Prussia |
| Conquest of the Desert | 30,000–35,000 | 1870s–1884 | Argentina vs. Mapuche people | Patagonia |
| Aceh War | 97,000–107,000 | 1873–1914 | Kingdom of the Netherlands vs. Aceh Sultanate | Indonesia |
| First Sino–Japanese War | 48,311+ | 1894–1895 | Qing China vs. Japan | East Asia |
| Cuban War of Independence | 362,000+ | 1895–1898 | USA and Cuba vs. Spain | Cuba |
| War of Canudos | 30,000+ | 1896-1897 | First Brazilian Republic vs. Canudos inhabitants | Brazil |
| Thousand Days’ War | 120,000+ | 1899–1902 | Colombian Conservatives vs. Colombian Liberals | Colombia |
| Boxer Rebellion | 100,000 | 1899–1901 | Boxers vs. Foreign powers | China |
| South African War (Second Boer War) | 73,000–90,000 | 1899-1902 | United Kingdom and allies vs. South African Republic and Orange Free State | South Africa |
| Philippine–American War | 234,000+ | 1899–1912 | Philippines vs. USA | Philippines |
| Russo-Japanese War | 101,300–206,100 | 1904–1905 | Russia vs. Japan | Northeast Asia |
| Mexican Revolution | 500,000–2,000,000 | 1910–1920 | In reality, a full blown Civil War with multiple sides | Mexico |
| 1911 Revolution | 220,000 | 1911 | Qing China vs. Revolutionaries | China |
| Balkan Wars | 140,000+ | 1912–1913 | Serbia, Montenegro and Bulgaria against the Ottoman Empire | Balkan Peninsula |
| World War I | 16,000,000–40,000,000+ (the higher estimate also includes the first victims of the related Spanish flu epidemic who died by the end of 1918. Neither includes the subsequent Russian Civil War) | 1914–1918 | Allied Powers vs. Central Powers | Worldwide |
| Russian Civil War | 5,000,000–9,000,000 | 1917–1922 | Red army and allies vs. White army and allies | Russia |
| Kurdish separatism in Iran | 15,000–58,000 | 1918–present | Qajar dynasty vs. Shekak (tribe) | Iran |
| Iraqi–Kurdish conflict | 138,800–320,100 | 1918–2003 | Kurdistan/Iraqi Kurdistan and allies vs. Iraq and allies | Iraq |
| Rif War | 30,500+ | 1921–1926 | Spain vs. Republic of the Rif | Morocco |
| Kurdish–Turkish conflict | 100,000+ | 1921–present | Turkey vs. Kurdish people | Middle East |
| Second Italo-Senussi War | 40,000+ | 1923–1932 | Italy vs. Senussi Order | Libya |
| Chinese Civil War | 8,000,000–11,692,000 | 1927–1949 | ROC vs. PRC | China |
| Chaco War | 85,000–130,000 | 1932–1935 | Bolivia vs. Paraguay | Gran Chaco |
| Second Italo–Ethiopian War | 278,000+ | 1935–1936 | Ethiopian Empire vs. Italy | Ethiopia |
| Spanish Civil War | 500,000–1,000,000 | 1936–1939 | Nationalists vs. Republicans | Spain |
| Second Sino-Japanese War | 20,000,000–25,000,000 | 1937–1945 | Republic of China and allies vs. Japan | China |
| World War II | 85,000,000 | 1939–1945 | Allied powers vs. Axis Powers | Worldwide |
| Winter War | 153,736–194,837 | 1939–1940 | Finland vs. Soviet Union | Finland |
| Greco-Italian War | 27,000+ | 1940–1941 | Greece vs. Italy | Southeast Europe |
| Continuation War | 387,300+ | 1941–1944 | Finland and Germany vs. Soviet Union | Northern Europe |
| Soviet–Japanese War | 33,420–95,768 | 1945 | Soviet Union and Mongolia vs. Japan | Manchuria |
| First Indochina War | 400,000+ | 1946–1954 | France vs. Việt Minh, Lao Assara, and Khmer Issarak | Southeast Asia |
| Partition of India | 200,000–2,000,000 | 1946–1948 | India and Pakistan | South Asia |
| Greek Civil War | 158,000+ | 1946–1949 | Greek Government army vs. DSE | Greece |
| Malagasy Uprising | 11,342–89,000 | 1947–1948 | France vs. Malagasy Insurgents | Madagascar |
| Kashmir conflict | 80,000–110,000 | 1947–present | India vs. Pakistan | North India / Pakistan |
| La Violencia | 192,700–194,700 | 1948–1958 | Colombian Conservative Party vs. Colombian Liberal Party | Colombia |
| Internal conflict in Myanmar | 130,000–250,000 | 1948–present | Myanmar vs. Burmese Insurgent Groups | Myanmar |
| Arab–Israeli conflict | 116,074+ | 1948–present | Arab Countries vs. Israel | Middle East |
| Annexation of Hyderabad | 29,000–242,000 | 1948 | Dominion of India vs. Hyderabad | India |
| Korean War | 1,500,000–4,500,000 | 1950–1953 | South Korea and allies vs. North Korea and allies | Korea |
| Algerian War | 400,000–1,500,000 | 1954–1962 | Algeria vs. France | Algeria |
| Ethnic conflict in Nagaland | 34,000+ | 1954–present | India and Myanmar vs. Naga People | Northeast India |
| Vietnam War | 1,300,000–4,300,000 | 1955–1975 | South Vietnam and allies vs. North Vietnam and allies | Vietnam |
| First Sudanese Civil War | 500,000+ | 1955–1972 | Sudan vs. South Sudanese Rebels | Sudan |
| Congo Crisis | 100,000+ | 1960–1965 | DRC, USA, and Belgium vs. Simba and Kwilu Rebels | Congo |
| Angolan War of Independence | 83,000–103,000 | 1961–1974 | Angola vs. Portugal and South Africa | Angola |
| North Yemen Civil War | 100,000–200,000 | 1962–1970 | Kingdom of Yemen and Saudi Arabia vs. Yemen Arab Republic and United Arab Republic | Yemen |
| Mozambican War of Independence | 63,500–88,500 | 1964–1974 | FRELIMO vs. Portugal | Mozambique |
| Insurgency in Northeast India | 25,000+ | 1964–present | India and allies vs. Insurgent Groups | Northeast India |
| Colombian conflict | 220,000+ | 1964–present | Colombia and allies vs. Far Left guerillas and Far Right paramilitares | Colombia |
| Nigerian Civil War | 1,000,000–3,000,000 | 1967–1970 | Nigeria vs. Biafra | Nigeria |
| Moro conflict | 120,000+ | 1969–2019 | Philippines vs. Jihadist Groups vs. Bangsamoro | Philippines |
| Communist rebellion in the Philippines | 30,000–43,000 | 1969–present | Philippines vs. Communist Party of the Philippines | Philippines |
| Bangladesh Liberation War | 300,000–3,000,000+ | 1971 | India and Bangladesh vs. Pakistan | Bangladesh |
| Ethiopian Civil War | 500,000–1,500,000 | 1974–1991 | Derg, PEDR, and Cuba vs. Anti-Communist rebel groups | Ethiopia |
| Angolan Civil War | 504,158+ | 1975–2002 | MPLA vs. UNITA | Angola |
| Lebanese Civil War | 120,000–150,000 | 1975–1990 | Various groups | Lebanon |
| Insurgency in Laos | 100,000+ | 1975–2007 | Laos and Vietnam vs. “Secret army” and Hmong people | Laos |
| Afghanistan conflict | 1,400,000–2,000,000 | 1978–present | Afghan mujahideen vs URSS then USA | Afghanistan |
| Kurdish–Turkish conflict | 45,000+ | 1978–present | Turkey vs. KCK | Middle East |
| Soviet–Afghan War | 600,000–2,000,000 | 1979–1989 | Soviet Union and Afghanistan vs. Insurgent groups | Afghanistan |
| Salvadoran Civil War | 70,000–80,000 | 1979–1992 | El Salvador vs. FMLN | El Salvador |
| Iran–Iraq War | 500,000 | 1980–1988 | Iran and allies vs. Iraq and allies | Middle East |
| Internal conflict in Peru | 70,000+ | 1980–present | Peru vs. PCP-SL and MRTA | Peru |
| Ugandan Bush War | 100,000–500,000 | 1981–1986 | ULNF and Tanzania vs. National Resistance Army | Uganda |
| Second Sudanese Civil War | 1,000,000–2,000,000 | 1983–2005 | Sudan vs. South Sudanese rebels | Sudan |
| Sri Lankan Civil War | 80,000–100,000 | 1983–2009 | Sri Lanka vs. Tamil Tigers | Sri Lanka |
| Somali Civil War | 300,000–500,000 | 1986–present | Varying Somali governments vs. insurgent groups | Somalia |
| Lord’s Resistance Army insurgency | 100,000–500,000 | 1987–present | Lord’s Resistance Army vs. Central African states | Central Africa |
| Nagorno-Karabakh conflict | 50,000+ | 1988–present | Armenia, Nagorno-Karabakh Separatist forces and allies vs. Azerbaijan | Azerbaijan |
| Gulf War | 25,500–40,500 | 1990–1991 | Iraq vs. Coalition Forces | Iraq |
| Algerian Civil War | 44,000–200,000 | 1991–2002 | Algeria vs. FIS loyalists vs. GIA | Algeria |
| Bosnian War | 97,000–105,000 | 1991–1995 | Bosnia and Herzegovinian governments and allies vs. Republika Srpska and allies | Bosnia |
| 1991 Iraqi uprisings | 85,000–235,000 | 1991 | Iraq vs various rebels | Iraq |
| Sierra Leone Civil War | 50,000–300,000 | 1991–2002 | Sierra Leone | |
| Burundian Civil War | 300,000+ | 1993–2005 | Burundi vs. Hutu rebels vs. Tutsi rebels | Burundi |
| Rwandan genocide | 800,000 | April–July 1994 | Hutu people vs. Tutsi Rebels | Rwanda |
| First Congo War | 250,000–800,000 | 1996–1997 | Zaire and allies vs. AFDL and allies | Congo |
| Second Congo War | 2,500,000–5,400,000 | 1998–2003 | Central Africa | |
| Ituri conflict | 60,000+ | 1999–2003 | Lendu Tribe vs. Hemu Tribe and allies | Congo |
Modern (2000-present) wars with greater than 25,000 deaths
| War | Death range | Date | Combatants | Location |
| War on terror | 272,000–1,260,000 | 2001–present | Anti-Terrorist Forces vs. Terrorist groups | Worldwide |
| War in Afghanistan (2001–2021) | 212,191+ | 2001–2021 | Afghanistan | |
| Iraq War | 405,000–654,965 | 2003–2011 | Iraq vs USA | Iraq |
| War in Darfur | 300,000+ | 2003–present | SRF and allies vs. Sudan and allies vs. UNAMID | Sudan |
| Kivu Conflict | 100,000+ | 2004–present | see Kivu Conflict | Congo |
| Insurgency in Khyber Pakhtunkhwa | 45,900–79,000 | 2004–2017 | Pakistan, USA, and UK vs. Terrorist groups | Pakistan |
| Mexican drug war | 150,000–250,000 | 2006–present | Mexico vs. Drug cartels | Mexico |
| Boko Haram insurgency | 350,000+ | 2009–present | Multinational Joint Task Force vs. Boko Haram | Nigeria |
| Syrian civil war | 499,000–610,000+ | 2011–present | Syrian Arab Republic vs. Republic of Syria vs. ISIL vs. Syrian Democratic Forces | Syria |
| Rojava–Islamist conflict | 50,000+ | 2013–present | Syrian Democratic Forces vs. Islamic States of Iraq and Levant vs. al-Nusra Front | Syria |
| War in Iraq (2013–2017) | 195,000–200,000+ | 2013–2017 | Iraq and allies vs. ISIL | Iraq |
| Yemeni Civil War | 377,000+ | 2014–present | Yemen’s Supreme Political Council vs. Hadi Government, Saudi-led Coalition and the UAE-backed Southern Movement vs Al-Qaeda | Yemen |
| Russo-Ukrainian War | 23,000–200,000 | 2014–present | Russia vs. Ukraine | Ukraine |
| Tigray War | 300,000–500,000 | 2020–present | UFEFCF vs. Ethiopian and Eritrean Government | Ethiopia (Tigray, Afar and Amhara Regions) |
