- May 7 Gerhard Moritz Roentgen, Dutch industrialist (founder of Fijenoord dockyard), born in Esen, East Frisia (d. 1852)
- May 10 Jacques-Nicolas-Augustin Thierry, French historian, born in Blois, France (d. 1856)
- May 13 Gérard Paul Deshayes, French geologist (d. 1875)
- May 13 Joshua Ratoon Sands, American Rear Admiral (Union Navy), born in Brooklyn, New York (d. 1883)
- May 15 Adolf Bernhard Marx [Samuel Moses Marx], German music theorist and pedagogue, born in Halle, Duchy of Magdeburg, Holy Roman Empire (now Germany) (d. 1866)
- May 19 Johns Hopkins, American financier and philanthropist (founded Johns Hopkins Hospital and Johns Hopkins University), born in Gambrills, Maryland (d. 1873)
- May 23 Charles Barry, British architect, born in London (d. 1860)
20-29
30-39
40-49
50-59
80-89
Over 90