- May 2 Frederic Cliffe, English composer, born in Bradford, Yorkshire, England (d. 1931)
- May 3 George Gore, American baseball player, born in Saccarappa, Maine (d. 1933)
- May 5 Lee Richmond, American baseball pitcher (first ever MLB perfect game 1880), born in Sheffield, Ohio (d. 1929)
- May 7 William A. MacCorkle, American politician, 90th Governor of West Virginia, born in Lexington, Virginia (d. 1930)
- May 8 Frederik "Frits" Tartaud, Dutch acto,r and husband of Dutch actress Alida Klein, born in Amsterdam, Netherlands (d. 1946)
- May 9 Luigi Illica, Italian poet and opera librettist (Giacomo Puccini's "La bohème", "Tosca", and "Madama Butterfly"; Umberto Giordano's "Andrea Chénier"), born in Castell'Arquato, Duchy of Parma and Piacenza (d. 1919)
- May 10 Hendrik Zwaardemaker, Dutch physiologist (invented the olfactometer), born in Haarlem, Netherlands (d. 1930)
- May 13 Ronald Ross, British pathologist (Nobel Prize 1902), born in Almora, North-Western Provinces, British India (d. 1932)
- May 15 Williamina Fleming, Scottish-born astronomer (d. 1911)
- May 16 Juan Morel Campos, Puerto Rican composer (Danza), born in Ponce, Puerto Rico (d. 1896)
- May 19 John Jacob Abel, American pharmacologist (endocrine glands), born in Cleveland, Ohio (d. 1938)
Pius XI (1857-1939)
May 31 Italian 259th Pope (1922-39), born in Desio, Lombardy-Venetia, Austrian Empire
20-29
30-39
40-49
50-59
80-89
Over 90