| 1800–1850 | USA [consumer products] | A revolution in retail and wholesale trade occurs: specialization transforms the urban retail market, replacing the general store with individual stores for hardware, groceries, dry goods, furnishing, books, tobacco, and so on. Cash-only sales policies are instituted around 1806. |
| 1810–1859 | USA [agriculture] | US cotton production, the vast majority of which is grown in the southern states, rises from 171,000 bales in 1810 to just under 5.4 million in 1859. |
| 1840–1850 | USA [farming] | Wheat becomes an increasingly important cash crop in the USA; production in 1839 is nearly 85 million bushels and climbs to over 100 million bushels in 10 years. |
| 1840–1860 | world [plagues and epidemics] | A cholera pandemic kills millions of people worldwide. |
| 1841–1850 | USA, UK [statistics and demography] | Emigration to the USA is 267,044 from Britain and 780,719 from Ireland. |
| 1845–1958 | Germany [earth sciences] | German naturalist and explorer Alexander von Humboldt lays the basis of modern geography with the publication of Kosmos/Cosmos, in which he arranges geographic knowledge in a systematic fashion. |
| 1846 | UK [famines] | The Irish potato crop fails again, as in 1845, and famine increases despite organized relief. |
| 1846 | Germany [orchestral music] | German composer Felix Mendelssohn completes his oratorio Elias/Elijah (Opus 70). It is first performed in Birmingham, England, in 1846. |
| 1846 | USA [fiction] | The US writer Nathaniel Hawthorne publishes his story collection Mosses From an Old Manse, which includes ‘Young Goodman Brown’ and ‘Rappaccini's Daughter’. |
| 1846 | France [fiction] | The French writer Honoré de Balzac publishes his novel La Cousine Bette/Cousin Bette. |
| 1846 | Natal [law and government] | The beginnings of native segregation are seen in the British colony of Natal, southern Africa, where the first location commission sets up preserves for immigrant Zulus. |
| 1846 | USA [business and economics] | Alexander Turney Stewart opens the Marble Dry Goods Palace on Broadway in New York City. It is the first department store and the largest shop in the world. |
| 1846 | Italy [chemistry] | Italian chemist Ascanio Sobrero is the first to prepare the powerful explosive nitroglycerine. |
| 1846 | France [solo and chamber music] | The French composer Hector Berlioz completes his dramatic cantata La Damnation de Faust/The Damnation of Faust (Opus 24), based on Goethe's play Faust, written in 1808. Berlioz began work on this piece in 1828. |
| 1846 | England [zoology] | The English palaeontologist Richard Owen publishes Lectures on Comparative Anatomy and Physiology of the Vertebrate Animals, one of the first textbooks on comparative vertebrate anatomy. |
| 21 January 1846 | UK [newspapers] | The Daily News is founded in London, England, with the author Charles Dickens as editor. It is the first cheap daily newspaper in Britain. |
| 9 March 1846 | India, UK [treaties] | By the Treaty of Lahore ending the First Anglo-Sikh War in India, Britain gains territory beyond the Sutlej River, the previous boundary of British India. Punjab becomes a British protectorate. |
| 13 May 1846 | USA, Mexico [wars] | The USA makes a formal declaration of war against Mexico over the disputed territory of New Mexico. |
| 6 June 1846 | USA [religious freedom] | Mormon Church leader Brigham Young, who replaced the murdered Joseph Smith, leads his followers out of Nauvoo, Illinois, to escape persecution. They set out for the Great Salt Lake in Utah in what becomes known as the Mormon migration. |
| 15 June 1846 | Papal States [Catholicism] | Cardinal Mastai-Ferretti, at this time regarded as a liberal, is elected Pope Pius IX. |
| 19 June 1846 | USA [baseball] | In what is regarded as the first real baseball game (played under the rules modified in 1845 by the Knickerbocker Club) the Knickerbocker Club play the New York Club at the Elysian Fields, Hoboken, New Jersey. |
| 26 June 1846 | UK [taxation] | The British prime minister, Robert Peel, repeals the Corn Laws to allow the unhindered importation of grain into Ireland in an effort to alleviate the famine caused there by the failure of the potato crop. His Conservative Party wants to retain the Corn Laws to protect the position of the landed elite and splits over the issue. |
| 27 June 1846 | Ireland [births and deaths] | Charles Stewart Parnell, Irish nationalist who leads the movement for Irish home rule, born in Avondale, County Wicklow, Ireland (–1891). |
| 10 September 1846 | USA [technology] | US inventor Elias Howe patents a practical sewing machine; it revolutionizes garment manufacture in both the factory and home. |
| 23 September 1846 | Germany [astronomy] | German astronomer Johann Gottfried Galle discovers the planet Neptune on the basis of French astronomer Urbain Le Verrier's calculations of its position. |
| 30 September 1846 | USA [dentistry] | US dentist William Thomas Morton gives the first successful demonstration of ether as an anaesthetic during a dental operation to extract a tooth. He uses it in Boston, Massachusetts, on 16 October, to anaesthetize a patient while removing a tumour from his neck. |
| 10 October 1846 | Spain, France [political events] | Queen Isabella II of Spain is married to the Duke of Cadiz, Don Francisco de Asis, while her sister Princess Maria Louisa Fernanda marries the duc de Montpensier, the youngest son of the French king, Louis Philippe, giving France undue influence in Spain. Fears of British opposition to the marriages weaken the Orléanist monarchy in France. |
