| 89965 | August 9 | Event | 1942 – Indian leader Mahatma Gandhi is arrested in Bombay by British forces, launching the Quit India Movement. |
| 89966 | August 9 | Event | 1942 – World War II: Battle of Savo Island – Allied naval forces protecting their amphibious forces during the initial stages of the Battle of Guadalcanal are surprised and defeated by an Imperial Japanese Navy cruiser force. |
| 89967 | August 9 | Event | 1944 – The United States Forest Service and the Wartime Advertising Council release posters featuring Smokey Bear for the first time. |
| 89968 | August 9 | Event | 1944 – Continuation War: The Vyborg–Petrozavodsk Offensive, the largest offensive launched by Soviet Union against Finland during the Second World War, ends to a strategic stalemate. Both Finnish and Soviet troops at the Finnish front dug to defensive pos |
| 89969 | August 9 | Event | 1945 – World War II: Nagasaki is devastated when an atomic bomb, Fat Man, is dropped by the United States B-29 Bockscar. 35,000 people are killed outright, including 23,200-28,200 Japanese war workers, 2,000 Korean forced workers, and 150 Japanese soldier |
| 89970 | August 9 | Event | 1945 – The Red Army invades Japanese-occupied Manchuria. |
| 89941 | August 8 | Holiday and observance | Farmer's Day or Nane Nane, Swahili for "8-8". (Tanzania) |
| 89942 | August 8 | Holiday and observance | Father's Day or Bā bā Day (爸爸節), Bā Bā is Mandarin for "father" and "8-8", or August 8. (Taiwan) |
| 89943 | August 8 | Holiday and observance | Flag Day (Sweden), namesday of Queen Silvia. (Sweden) |
| 89944 | August 8 | Holiday and observance | Signal Troops Day (Ukraine) |
| 89945 | August 9 | Event | 48 BC – Caesar's Civil War: Battle of Pharsalus – Julius Caesar decisively defeats Pompey at Pharsalus and Pompey flees to Egypt. |
| 89946 | August 9 | Event | 378 – Gothic War: Battle of Adrianople – A large Roman army led by Emperor Valens is defeated by the Visigoths. Valens is killed along with over half of his army. |
| 89947 | August 9 | Event | 1173 – Construction of the campanile of the Cathedral of Pisa (now known as the Leaning Tower of Pisa) begins it will take two centuries to complete. |
| 89948 | August 9 | Event | 1329 – Quilon, the first Indian Christian Diocese, is erected by Pope John XXII the French-born Jordanus is appointed the first Bishop. |
| 89949 | August 9 | Event | 1483 – Opening of the Sistine Chapel in Rome with the celebration of a Mass. |
| 89950 | August 9 | Event | 1500 – Ottoman–Venetian War (1499–1503): The Ottomans capture Methoni, Messenia. |
| 89951 | August 9 | Event | 1610 – The First Anglo-Powhatan War begins in colonial Virginia. |
| 89952 | August 9 | Event | 1810 – Napoleon annexes Westphalia as part of the First French Empire. |
| 89953 | August 9 | Event | 1814 – Indian Wars: the Creek sign the Treaty of Fort Jackson, giving up huge parts of Alabama and Georgia. |
| 89954 | August 9 | Event | 1842 – The Webster–Ashburton Treaty is signed, establishing the United States–Canada border east of the Rocky Mountains. |
| 89955 | August 9 | Event | 1854 – Henry David Thoreau publishes Walden. |
| 89956 | August 9 | Event | 1862 – American Civil War: Battle of Cedar Mountain – At Cedar Mountain, Virginia, Confederate General Stonewall Jackson narrowly defeats Union forces under General John Pope. |
| 89957 | August 9 | Event | 1877 – Indian Wars: Battle of the Big Hole – A small band of Nez Percé Indians clash with the United States Army |
| 89958 | August 9 | Event | 1892 – Thomas Edison receives a patent for a two-way telegraph. |
| 89959 | August 9 | Event | 1902 – Edward VII and Alexandra of Denmark are crowned King and Queen of the United Kingdom of Great Britain and Ireland. |
| 89960 | August 9 | Event | 1907 – The first Boy Scout encampment concludes at Brownsea Island in southern England. |
| 89961 | August 9 | Event | 1914 – Start of the Battle of Mulhouse, part of a French attempt to recover the province of Alsace and the first French offensive of World War I. |
| 89962 | August 9 | Event | 1925 – A train robbery takes place in Kakori, near Lucknow, India |
| 89963 | August 9 | Event | 1930 – Betty Boop makes her cartoon debut in Dizzy Dishes. |
| 89964 | August 9 | Event | 1936 – Summer Olympic Games: Games of the XI Olympiad – Jesse Owens wins his fourth gold medal at the games. |