Wars of the 19th Century

From the renewal of war in 1803 to Waterloo in 1815, Napoleonic France and shifting coalitions fought across Europe, the Atlantic, and the Mediterranean. French rule spread legal and administrative reforms alongside conscription, occupation, and extraction; resistance and coalition warfare fostered competing national movements. Napoleon abdicated in 1814, briefly returned in 1815, and was exiled after Waterloo.

14 battles · 6,500,000 dead

The United States declared war on Britain amid disputes over maritime restrictions and impressment, expansionist aims toward Canada, and conflict over Indigenous resistance to U.S. settlement. The Treaty of Ghent restored the Anglo-American territorial status quo and did not resolve every stated cause. For many Native nations the outcome was disastrous: Britain abandoned demands for an Indigenous buffer state, and U.S. expansion accelerated.

11 battles · 23,000 dead

Two wars in which Britain, joined by France in the second, used military force to expand commerce and diplomatic access in Qing China after Chinese officials tried to suppress the illegal opium trade. The 1842 Treaty of Nanjing opened treaty ports and ceded Hong Kong but did not legalize opium; legalization followed the Second Opium War through the 1858 treaty-and-tariff settlement. The unequal treaties imposed new privileges on foreign powers and became central to Chinese memories of nineteenth-century imperial coercion.

13 battles · 23,000 dead

A war of territorial expansion begun after the United States annexed Texas and President James K. Polk sent troops into the disputed land between the Nueces River and Rio Grande. Following a clash there, Congress declared war in May 1846. U.S. armies invaded northern and central Mexico and occupied Mexico City; the Treaty of Guadalupe Hidalgo ended the war under occupation and transferred an enormous territory to the United States, while promising rights to Mexican residents that were often eroded afterward.

11 battles · 54,283 dead

The Taiping Rebellion was among the deadliest civil wars in history, although estimates of its toll vary enormously. Hong Xiuquan, a repeatedly unsuccessful examination candidate who came to believe he was the younger brother of Jesus Christ, led a millenarian movement that captured Nanjing in 1853 and established the Taiping Heavenly Kingdom. Taiping leaders proclaimed radical religious and social programs, but implementation was uneven and the regime was internally divided. The Qing survived by relying increasingly on regional armies led by Zeng Guofan and Li Hongzhang, while foreign-trained forces including the Ever Victorious Army defended Shanghai. The fall of Nanjing in 1864 ended the Taiping capital amid mass killing, displacement, famine, and epidemic disease across devastated provinces.

7 battles · 25,000,000 dead

The Crimean War pitted Russia against the Ottoman Empire and an allied coalition led by Britain and France, with most famous operations fought on the Crimean Peninsula. Steamships, telegraphy, photography, and newspaper reporting made the conflict unusually immediate to distant publics, but calling it the first media war is a useful shorthand rather than a settled first. William Howard Russell became an influential civilian correspondent rather than a modern embedded reporter. Disease killed far more soldiers than combat. Florence Nightingale's nursing and statistical work became emblematic of reform, alongside the Sanitary Commission, Mary Seacole, and many less celebrated caregivers.

12 battles · 500,000 dead

The uprising of 1857 was a regionally concentrated but diverse military and civil rebellion against East India Company rule in much of northern and central India. Greased-cartridge fears helped trigger sepoy mutinies, but annexation, military service grievances, land and revenue policies, and fears of religious and social interference widened the revolt. Rebels restored the Mughal emperor Bahadur Shah Zafar as a symbolic sovereign in Delhi, while different leaders pursued local aims rather than a single national program. Rebel forces killed British soldiers and civilians, including at Kanpur; British reconquest involved extensive collective punishment, village destruction, summary execution, and reprisals. The Crown replaced Company rule in 1858. Later nationalists remembered the conflict as a First War of Independence, a retrospective interpretation rather than a description shared by all participants in 1857.

6 battles · 898,000 dead

A catalogue umbrella for many distinct wars, invasions, massacres, and campaigns between the United States and sovereign Native nations in the West, not a single continuous or unified conflict. U.S. expansion repeatedly violated or compelled treaties and sought Native land, while Indigenous peoples pursued different strategies of armed resistance, diplomacy, migration, and accommodation. Federal forces and settler militias destroyed villages and food systems and confined survivors to reservations; disease, starvation, forced removal, and attacks on civilians made the human cost far larger than recorded battlefield deaths.

11 battles · 103,000 dead

The bloodiest war in United States history began after eleven slaveholding states seceded to preserve slavery and formed the Confederate States of America. The Union initially fought to restore the United States, while emancipation became a formal war aim in 1863 and Black military service transformed the struggle. Four years of industrial-scale warfare destroyed slavery but left unresolved contests over citizenship, federal power, white supremacy, and the meaning of freedom during Reconstruction.

21 battles · 670,000 dead

A short war that overthrew Napoleon III, completed German unification under Prussian leadership, and established a new French republic. Bismarck edited publication of the Ems Dispatch to inflame the crisis, but the French declaration of war and the conflict’s origins cannot be reduced to a single act of engineering. German armies captured Napoleon III at Sedan and besieged Paris; the German Empire was proclaimed at Versailles in January 1871. The Treaty of Frankfurt transferred most of Alsace and part of Lorraine and imposed a large indemnity, leaving a durable grievance without making the First World War inevitable. Defeat and siege also helped produce the Paris Commune, whose suppression during Bloody Week killed thousands; the exact toll remains disputed.

9 battles · 239,000 dead

Russia invaded the Ottoman Empire in 1877 in a war presented as protection and liberation of Balkan Christians but also driven by imperial rivalry and Russian strategic aims. Russian, Romanian, and allied forces overcame Ottoman resistance at Plevna and Shipka and reached San Stefano near Constantinople. The preliminary Treaty of San Stefano proposed a large Bulgarian state, but the Congress of Berlin replaced it with an autonomous Bulgarian principality under nominal Ottoman suzerainty, while recognizing the independence of Romania, Serbia, and Montenegro. Violence, forced migration, and retaliation uprooted large Muslim and Christian populations, adding new grievances without making the First World War inevitable.

12 battles · 450,000 dead

Britain invaded the independent Zulu kingdom in January 1879 after imposing an ultimatum designed to be unacceptable, part of a wider effort to create a confederation in southern Africa. At Isandlwana a Zulu army destroyed much of the invading central column; later that day a separate Zulu force attacked the mission station at Rorke’s Drift, whose defense became central to British imperial memory. British reinforcements and firepower eventually defeated Cetshwayo’s army at Ulundi and dismantled the kingdom’s political order. Treating the war mainly as a contrast between a modern army and a pre-industrial enemy obscures Zulu statecraft, military organization, strategic choices, and the colonial aggression that began the conflict.

5 battles · 14,700 dead

A war among Chile, Peru, and Bolivia rooted in contested Atacama borders, nitrate wealth, rival commercial interests, treaty obligations, and a Bolivian tax dispute. Chile occupied the Bolivian port of Antofagasta before formal declarations of war, won command of the sea, invaded Peru, and occupied Lima. The settlements transferred nitrate-rich territory to Chile: Bolivia lost its sovereign Pacific coast and Peru ceded Tarapacá, while Tacna and Arica remained disputed for decades. The war’s occupation, guerrilla phase, and effects on Indigenous and civilian populations continued beyond the famous naval and set-piece battles.

11 battles · 70,000 dead

Two wars between the British Empire and the Boer republics of the Transvaal and Orange Free State, fought within a region whose Black African majority also experienced conscription, dispossession, displacement, and violence. The 1880–81 Transvaal War reversed Britain’s 1877 annexation after Boer victories including Majuba. The much larger South African War of 1899–1902 grew from competing sovereignty claims, mineral wealth, imperial expansion, and the Uitlander crisis. After conventional Boer defeat, commandos continued a mobile guerrilla war; British forces answered with farm destruction, forced removals, blockhouses, and segregated concentration camps. More than 27,000 Boer civilians and at least 14,000 Black Africans died in camps, with Black records incomplete. The Treaty of Vereeniging ended republican independence while laying foundations for a white-dominated union.

12 battles · 77,000 dead

A Sudanese revolutionary and religious movement led by Muhammad Ahmad, who proclaimed himself the Mahdi, overthrew much of the Turco-Egyptian colonial order amid grievances over taxation, slave-trade suppression, official abuses, and foreign domination. Mahdist forces destroyed several Egyptian-led armies and captured Khartoum in 1885, killing Charles Gordon during the city’s fall. The successor Khalifa Abdallahi governed an independent Mahdist state under severe military, environmental, and economic pressures. From 1896 an Anglo-Egyptian army under Kitchener used railways, gunboats, artillery, and mass firepower to reconquer Sudan. Omdurman was a devastating defeat, but reducing Sudanese fighters to “dervishes” or the campaign to a Gordon revenge story reproduces contemporary imperial propaganda.

11 battles · 110,000 dead

A brief war between Spain and the United States fought within longer Cuban and Philippine struggles for independence. Spanish reconcentration policy, U.S. strategic and economic interests, public pressure, and the unresolved explosion of USS Maine all shaped intervention; the sinking alone did not “spark” war in a simple causal sense. U.S. forces and local independence armies defeated Spain in Cuba and the Philippines. The Treaty of Paris ended Spanish rule, but excluded Cuban and Filipino representatives: the United States occupied Cuba and acquired Puerto Rico, Guam, and the Philippines, leading directly into colonial rule and the Philippine-American War.

11 battles · 463,289 dead

The Yihequan, labeled “Boxers” by foreigners, grew from rural religious and martial traditions amid drought, economic disruption, missionary disputes, Christian privilege, and accelerating foreign encroachment. Boxer groups attacked Chinese Christians, missionaries, and foreign property. The Qing court was divided: it first tried suppression, then supported the movement and declared war on foreign powers as legations and the Beitang were besieged. An eight-power expedition occupied Beijing and conducted widespread looting, rape, killing, and punitive expeditions. The 1901 Boxer Protocol imposed executions, foreign garrisons, and a huge indemnity, further weakening—but not mechanically determining the fall of—the Qing state.

10 battles · 125,000 dead

After Filipino revolutionaries declared independence from Spain and established the First Philippine Republic, the United States refused to recognize it and claimed sovereignty under the Treaty of Paris, whose negotiations excluded Filipinos. Fighting began around Manila in February 1899 and shifted from conventional campaigns to fragmented guerrilla resistance. U.S. forces used population concentration, food destruction, torture, and retaliatory violence; Filipino forces also killed prisoners and alleged collaborators. The war’s formal U.S. endpoint in 1902 did not end resistance everywhere. More than 4,200 U.S. troops and perhaps 20,000 Filipino combatants died, while violence, famine, and disease killed an estimated 200,000 civilians or more.

14 battles · 224,200 dead