Historical Events
- May 1 The Fraternity of Phi Gamma Delta is founded at Jefferson College in Canonsburg, Pennsylvania
- May 6 Otto Tank ends slavery in Suriname colony
- May 7 Prussians stop insurrection in Varsovia
- May 13 First performance of Finland's national anthem "Maamme", composed by Fredrik Pacius, Swedish words by Johan Ludvig Runeberg
- May 17 Gerrit, Count Schimmelpenninck resigns as Chairman of the Council of Ministers of Netherlands
- May 18 Opening of the first German National Assembly (Nationalversammlung) in Frankfurt, Germany
- May 29 Battle at Curtazone: Austrians beat Sardinia-Piemonte
- May 29 Wisconsin becomes 30th US state
- May 30 Second Battle at Gioto: Sardinia-Piemonte beats Austrians
- May 30 Treaty of Guadalupe Hidalgo between US and Mexico comes into force, giving California Nevada, Utah and most of Colorado, New Mexico and Arizona to the US in return for $15 million
- May 30 William G Young patents ice cream freezer
Famous Birthdays
- May 5 Adalbert von Goldschmidt, Austrian composer, born in Vienna, Austrian Empire (d. 1906)
- May 12 Cyrill Kistler, German composer, educator, and music theorist, born in Großaitingen, Swabia, Germany (d. 1907)
- May 15 Viktor Vasnetsov, Russian painter (d. 1926)
- May 23 Helmuth von Moltke, German army general (German Chief of Staff at outbreak of WWI), born in Gersdorff, Mecklenburg (d. 1916)
- May 23 Maritcha Remond Lyons, American educator, civic leader, suffragist, and civil rights leader (co-founder of the Women's Loyal Union of New York and Brooklyn), born in New York City (d. 1929)
- May 23 Otto Lilienthal, German pioneer aviator (explored winged flight through gliders), born in Anklam, Prussia (d. 1896)
Famous Deaths
- May 11 Tom Cribb, English bare knuckle boxer (C'ship of England 1808-22), dies at 66
- May 18 William Leidesdorff, Mixed-race early Californian businessman, dies at 37
- May 25 Annette von Droste-Hülshoff, German writer (b. 1797)
- May 26 Vissarion Belinsky, Russian literary critic (Sovremennik) and influential Westernizer, dies of consumption at 36
- May 27 Princess Sophia of the United Kingdom, 5th daughter of King George III, dies at 70
- May 31 Eugénie de Guérin, French writer (b. 1805)
