| 82141 | July 20 | Birth | 1789 – Mahmud II, Ottoman sultan (d. 1839) |
| 82142 | July 20 | Birth | 1797 – Paweł Edmund Strzelecki, Polish geologist and explorer (d. 1873) |
| 82143 | July 20 | Birth | 1804 – Richard Owen, English biologist, anatomist, and paleontologist (d. 1892) |
| 82144 | July 20 | Birth | 1822 – Gregor Mendel, Czech geneticist and botanist (d. 1884) |
| 82145 | July 20 | Birth | 1838 – Augustin Daly, American playwright and manager (d. 1899) |
| 82146 | July 20 | Birth | 1838 – Sir George Trevelyan, 2nd Baronet, English civil servant and politician, Chancellor of the Duchy of Lancaster (d. 1928) |
| 82147 | July 20 | Birth | 1847 – Max Liebermann, German painter and academic (d. 1935) |
| 82148 | July 20 | Birth | 1849 – Robert Anderson Van Wyck, American lawyer and politician, 91st Mayor of New York City (d. 1918) |
| 82149 | July 20 | Birth | 1852 – Theo Heemskerk, Dutch lawyer and politician, Prime Minister of the Netherlands (d. 1932) |
| 82150 | July 20 | Birth | 1858 – Juan Vucetich, Croatian-Argentinian anthropologist and police officer (d. 1925) |
| 82151 | July 20 | Birth | 1864 – Erik Axel Karlfeldt, Swedish poet and academic, Nobel Prize laureate (d. 1931) |
| 82152 | July 20 | Birth | 1864 – Ruggero Oddi, Italian physiologist and anatomist (d. 1913) |
| 82153 | July 20 | Birth | 1868 – Miron Cristea, Romanian cleric and politician, 38th Prime Minister of Romania (d. 1939) |
| 82154 | July 20 | Birth | 1873 – Alberto Santos-Dumont, Brazilian pilot (d. 1932) |
| 82155 | July 20 | Birth | 1876 – Otto Blumenthal, German mathematician and academic (d. 1944) |
| 82156 | July 20 | Birth | 1889 – John Reith, 1st Baron Reith, Scottish broadcaster, co-founded BBC (d. 1971) |
| 82157 | July 20 | Birth | 1890 – Verna Felton, American actress and singer (d. 1966) |
| 82158 | July 20 | Birth | 1890 – Julie Vinter Hansen, Danish-Swiss astronomer and academic (d. 1960) |
| 82159 | July 20 | Birth | 1893 – George Llewelyn Davies, English soldier (d. 1915) |
| 82160 | July 20 | Birth | 1895 – László Moholy-Nagy, Hungarian painter, photographer, and sculptor (d. 1946) |
| 82161 | July 20 | Birth | 1896 – Eunice Sanborn, American super-centenarian (d. 2011) |
| 82162 | July 20 | Birth | 1897 – Tadeusz Reichstein, Polish-Swiss chemist and academic, Nobel Prize laureate (d. 1996) |
| 82163 | July 20 | Birth | 1900 – Maurice Leyland, English cricketer and coach (d. 1967) |
| 82164 | July 20 | Birth | 1901 – Vehbi Koç, Turkish businessman and philanthropist, founded Koç Holding (d. 1996) |
| 82165 | July 20 | Birth | 1901 – Heinie Manush, American baseball player and manager (d. 1971) |
| 82166 | July 20 | Birth | 1909 – Eric Rowan, South African cricketer (d. 1993) |
| 82167 | July 20 | Birth | 1910 – Vilém Tauský, Czech-English conductor and composer (d. 2004) |
| 82168 | July 20 | Birth | 1911 – Baqa Jilani, Indian cricketer (d. 1941) |
| 82169 | July 20 | Birth | 1911 – José Zabala-Santos, Filipino author and illustrator (d. 1985) |
| 82170 | July 20 | Birth | 1912 – George Johnston, Australian journalist and author (d. 1970) |