Historical Events
- May 2 Argentinian Domingo Sarmiento publishes his anti-tyranny work "Facundo Civilización y Barbarie"
- May 3 1st African American lawyer, Macon B. Allen, admitted to the bar in Massachusetts
- May 3 Fire kills 1,600 in a popular theater in Canton, China
- May 14 Utrecht-Arnhem Railway opens
- May 20 1st legislative assembly convenes in Hawaii
- May 20 HMS Erebus and HMS Terror with 134 men under John Franklin sail from the River Thames in England, beginning a disastrous expedition to find the Northwest Passage. All hands are lost.
- May 23 New York City Police Department (NYPD) is formed, replacing an old night watch system
- May 28 Fire in Quebec, Canada, 1,500 houses destroyed
Famous Birthdays
- May 1 [Robert] Lawson Tait, Scottish-born pioneering surgeon performed first salpingectomy for ectopic pregnancy, born in Edinburgh, Scotland (d. 1899)
- May 12 Gabriel Fauré, French organist, composer (Requiem; Ballade), and educator (Paris Conservatoire, 1905-20), born in Pamiers, France (d. 1924)
- May 15 Ilya Mechnikov, Russian zoologist and bacteriologist known as the "father of natural immunity" (Nobel 1908), born in Ivanovka, Kharkov Governorate, Russian Empire (d. 1916)
- May 25 Lip Pike, American baseball player, born in New York City (d. 1893)
- May 30 Amadeus/Amadeo I, duke of Aosta and King of Spain (1870-73), born in Turin, Italy (d. 1890)
Famous Deaths
- May 2 August Pauly, German writer (Real Encyclopedia), dies at 48
- May 3 Thomas Hood, English poet and composer (The Song of the Shirt), dies at 45
- May 11 Carl Filtsch, Transylvanian composer and pianist child prodigy, dies of tuberculosis at 14
- May 12 August Wilhelm Schlegel, German poet, translator and critic, dies at 77
- May 12 János Bacsanyi, Hungarian poet (b. 1763)
- May 15 Samuel Wiselius, Dutch lawyer patriot and writer (helped dismantle Dutch East India Co), dies at 76
- May 19 Maria EJ Versfelt, mistress of general Moreau/marshal Ney, dies at 68
