| 56821 | May.18 | Birth | 1797 – Frederick Augustus II of Saxony (d. 1854) |
| 56822 | May.18 | Birth | 1822 – Mathew Brady, American photographer and journalist (d. 1896) |
| 56823 | May.18 | Birth | 1850 – Oliver Heaviside, English engineer, mathematician, and physicist (d. 1925) |
| 56824 | May.18 | Birth | 1851 – James Budd, American lawyer and politician, 19th Governor of California (d. 1908) |
| 56825 | May.18 | Birth | 1852 – Gertrude Käsebier, American photographer (d. 1934) |
| 56826 | May.18 | Birth | 1854 – Bernard Zweers, Dutch composer and educator (d. 1924) |
| 56827 | May.18 | Birth | 1855 – Francis Bellamy, American minister and author (d. 1931) |
| 56828 | May.18 | Birth | 1862 – Josephus Daniels, American publisher and politician, 41st United States Secretary of the Navy (d. 1948) |
| 56829 | May.18 | Birth | 1868 – Nicholas II of Russia (d. 1918) |
| 56830 | May.18 | Birth | 1871 – Denis Horgan, Irish shot putter and weight thrower (d. 1922) |
| 56831 | May.18 | Birth | 1872 – Bertrand Russell, Welsh mathematician, historian, and philosopher, Nobel Prize laureate (d. 1970) |
| 56832 | May.18 | Birth | 1873 – Lucy Beaumont, English-American actress (d. 1937) |
| 56833 | May.18 | Birth | 1876 – Hermann Müller, German journalist and politician, 12th Chancellor of Germany (d. 1931) |
| 56834 | May.18 | Birth | 1878 – Johannes Terwogt, Dutch rower (d. 1977) |
| 56835 | May.18 | Birth | 1882 – Babe Adams, American baseball player, manager, and journalist (d. 1968) |
| 56836 | May.18 | Birth | 1883 – Eurico Gaspar Dutra, Brazilian marshal and politician, 16th President of Brazil (d. 1974) |
| 56837 | May.18 | Birth | 1883 – Walter Gropius, German-American architect, designed the John F. Kennedy Federal Building (d. 1969) |
| 56838 | May.18 | Birth | 1887 – Jeanie MacPherson, American actress and screenwriter (d. 1946) |
| 56839 | May.18 | Birth | 1889 – Thomas Midgley, Jr., American chemist and engineer (d. 1944) |
| 56840 | May.18 | Birth | 1891 – Rudolf Carnap, German-American philosopher and academic (d. 1970) |
| 56841 | May.18 | Birth | 1892 – Ezio Pinza, Italian-American actor and singer (d. 1957) |
| 56842 | May.18 | Birth | 1895 – Augusto César Sandino, Nicaraguan rebel leader (d. 1934) |
| 56843 | May.18 | Birth | 1896 – Eric Backman, Swedish runner (d. 1965) |
| 56844 | May.18 | Birth | 1897 – Frank Capra, Italian-American director, producer, and screenwriter (d. 1991) |
| 56845 | May.18 | Birth | 1898 – Faruk Nafiz Çamlıbel, Turkish poet, author, and playwright (d. 1973) |
| 56846 | May.18 | Birth | 1901 – Henri Sauguet, French composer (d. 1989) |
| 56847 | May.18 | Birth | 1901 – Vincent du Vigneaud, American biochemist and academic, Nobel Prize laureate (d. 1978) |
| 56848 | May.18 | Birth | 1902 – Meredith Willson, American playwright and composer (d. 1984) |
| 56849 | May.18 | Birth | 1904 – Shunryū Suzuki, Japanese-American monk and educator (d. 1971) |
| 56850 | May.18 | Birth | 1904 – Jacob K. Javits, American colonel and politician, 58th New York Attorney General (d. 1986) |