- May 8 Bryan Morel Thomas, Brigadier General (Confederate Army), born in Milledgeville, Georgia (d. 1905)
- May 14 James Patrick Major, Brigadier General (Confederate Army), (d. 1877)
- May 17 Sir Norman Lockyer, English physicist, co-founder of helium gas, founder and editor of "Nature" magazine, born in Rugby, Warwickshire (d. 1920)
- May 17 Virginie Loveling, Flemish writer (Sophie) and poet, born in Nevele, East Flanders, Belgium (d. 1923)
- May 17 Wilhelm Steinitz, Austrian World Chess Champion (1866-94), born in Prague, Bohemia, Austrian Empire (d. 1900)
- May 18 Sydir Vorobkevych, Ukrainian composer, poet, newspaper editor, and Orthodox priest, born in Chernivtsi, Ukraine (d. 1903)
- May 24 Joseph Rowntree, British social reformer, born in York, England (d. 1925)
- May 27 Edwin Gray Lee, American Brigadier General (Confederate Army), born in Shepherdstown, Virginia (d. 1870)
- May 27 Jay Gould, American railroad developer and speculator, born in Roxbury, New York (d. 1892)
- May 28 Alexander Mitscherlich, German chemist and son of Eilhard Mitscherlich, born in Berlin (d. 1918)
20-29
30-39
40-49
50-59
80-89
Over 90