The 1850s was the decade that began on January 1, 1850 and ended on December 31, 1859.
|Centuries:||18th century – 19th century – 20th century|
|Decades:||1820s 1830s 1840s – 1850s – 1860s 1870s 1880s|
|Years:||1850 1851 1852 1853 1854 1855 1856 1857 1858 1859|
|Categories:||Births – Deaths – Architecture|
Establishments – Disestablishments
- Production of steel revolutionised by invention of the Bessemer process
- Benjamin Silliman fractionates petroleum by distillation for the first time
- First transatlantic telegraph cable laid
- First safety elevator installed by Elisha Otis
- Charles Darwin publishes The Origin of Species, putting forward the theory of evolution by natural selection
- Epidemiology begins when John Snow traces the source of an outbreak of cholera in London to a contaminated water pump.
- Discovery of Neandertal fossils in Neanderthal, Germany
- Solar flares discovered by Richard Christopher Carrington
- Crimean War (1854–1856) fought between Imperial Russia and an alliance consisting of the United Kingdom of Great Britain and Ireland, the Second French Empire, the Kingdom of Sardinia and the Ottoman Empire. The majority of the conflict takes place around Crimea, on the northern coasts of the Black Sea.
- The Indian Mutiny: revolt against the East India Company's British rule in India
- Dissolution of the Mughal Empire by the British.
- 156 are killed in Paris in a failed assassination attempt on Napoleon III, Emperor of France
- Moldavia and Wallachia are unified and form Romania.
- Gideon T. Stewart attempts to create a Prohibition Party.
World leaders change
- Emperor Franz Josef (Austria-Hungary)
- Emperor Napoleon III (Second French Empire)
- King Frederick William IV (Germany)
- Pope Pius IX
- Queen Maria II (Portugal)
- King Peter V (Portugal)
- Emperor Nicholas I (Russia)
- Emperor Alexander II (Russia)
- Queen Isabella II (Spain)
- Queen Victoria, (United Kingdom)
- Prime Minister Lord John Russell (United Kingdom)
- Prime Minister Lord Aberdeen (United Kingdom)
- Prime Minister Lord Palmerston (United Kingdom)
- President Millard Fillmore (United States)
- President Franklin Pierce (United States)
- President James Buchanan (United States)
- Nasser-al-Din Shah of Qajar dynasty (Persia)