| 44971 | April 18 | Death | 1796 – Johan Wilcke, Swedish physicist and academic (b. 1732) |
| 44972 | April 18 | Death | 1802 – Erasmus Darwin, English physician and botanist (b. 1731) |
| 44973 | April 18 | Death | 1832 – Jeanne-Elisabeth Chaudet, French painter (b. 1761) |
| 44974 | April 18 | Death | 1859 – Tatya Tope, Indian general (b. 1814) |
| 44975 | April 18 | Death | 1864 – Juris Alunāns, Latvian philologist and linguist (b. 1832) |
| 44976 | April 18 | Death | 1873 – Justus von Liebig, German chemist and academic (b. 1803) |
| 44977 | April 18 | Death | 1898 – Gustave Moreau, French painter and academic (b. 1826) |
| 44978 | April 18 | Death | 1904 – Sumner Paine, American target shooter (b. 1868) |
| 44979 | April 18 | Death | 1906 – Luis Martín, Spanish religious leader, 24th Superior-General of the Society of Jesus (b. 1846) |
| 44980 | April 18 | Death | 1913 – Harrison Clark, American soldier (b. 1842) |
| 44981 | April 18 | Death | 1917 – Vladimir Serbsky, Russian psychiatrist and academic (b. 1858) |
| 44982 | April 18 | Death | 1936 – Milton Brown, American singer and bandleader (Light Crust Doughboys) (b. 1903) |
| 44983 | April 18 | Death | 1936 – Ottorino Respighi, Italian composer and conductor (b. 1879) |
| 44984 | April 18 | Death | 1938 – George Bryant, American archer (b. 1878) |
| 44985 | April 18 | Death | 1942 – Aleksander Mitt, Estonian speed skater (b. 1903) |
| 44986 | April 18 | Death | 1942 – Gertrude Vanderbilt Whitney, American sculptor and art collector, founded the Whitney Museum of American Art (b. 1875) |
| 44987 | April 18 | Death | 1943 – Isoroku Yamamoto, Japanese admiral (b. 1884) |
| 44988 | April 18 | Death | 1945 – John Ambrose Fleming, English physicist and engineer, invented the vacuum tube (b. 1849) |
| 44989 | April 18 | Death | 1945 – William, Prince of Albania (b. 1876) |
| 44990 | April 18 | Death | 1945 – Ernie Pyle, American journalist and soldier (b. 1900) |
| 44991 | April 18 | Death | 1947 – Jozef Tiso, Slovak priest and politician, President of Slovakia (b. 1887) |
| 44992 | April 18 | Death | 1949 – Will Hay, English actor and director (b. 1888) |
| 44993 | April 18 | Death | 1951 – Óscar Carmona, Portuguese field marshal and politician, 11th President of Portugal (b. 1869) |
| 44994 | April 18 | Death | 1955 – Albert Einstein, German-American physicist, engineer, and academic (b. 1879) |
| 44995 | April 18 | Death | 1958 – Maurice Gamelin, Belgian-French general (b. 1872) |
| 44996 | April 18 | Death | 1959 – Irving Cummings, American actor, director, and producer (b. 1888) |
| 44997 | April 18 | Death | 1959 – Percy Smith, English footballer and manager (b. 1880) |
| 44998 | April 18 | Death | 1963 – Meyer Jacobstein, American academic and politician (b. 1880) |
| 44999 | April 18 | Death | 1964 – Ben Hecht, American director, producer, and screenwriter (b. 1894) |
| 45000 | April 18 | Death | 1965 – Guillermo González Camarena, Mexican engineer (b. 1917) |