| 9 September 480 BC | Greece [Greek–Persian War (490 BC)] | The Greek city of Athens is besieged and burnt by the Persians, but the Athenians, under general Themistocles and Aristides, who has recently been recalled from exile, destroy the Persian fleet in a naval battle in the Bay of Salamis. The Persian army retires to winter in Thessaly. |
| 9 September 413 BC | Greece, Sicily [Peloponnesian War (431 BC)] | Despite the arrival of a second fleet under the command of the Athenian general Demosthenes, the Athenian expedition in Sicily is heavily defeated in a joint land and sea battle near Syracuse. The Athenian leaders Nicias and Demosthenes are captured and put to death; most of the surviving soldiers are sent to die in the Sicilian quarries. |
| 9 September 55 BC | Rome, UK [wars] | The Roman statesman and general Julius Caesar sails for Britain with two legions. He is content to do no more than show his superiority in arms, but it is received with popular acclaim in Rome. He lands, despite opposition, probably near modern Walmer, Kent. The Britons return the Roman ambassador Commius but sue for peace. However, when a high tide destroys some of Caesar's ships, they renew the fighting and Caesar, having made his point, recrosses the English Channel. |
| 9 September 951 | Italy, Germany [political events] | Adelaide, the widow of King Lothair II of Italy, appeals to the German king Otto I, later Holy Roman Emperor, for help against Berengar of Ivrea, who has imprisoned her. Otto invades Italy, takes the northern city of Pavia, marries Adelaide, and assumes the Italian crown. Berengar takes refuge in the Alps. |
| 9 September 961 | Italy, Germany [political events] | In answer to an appeal from Pope John XII for protection against King Berengar II of Ivrea, King Otto I of Germany invades Italy and, with his son Otto, is acknowledged as king of Italy on his capture of the northern city of Pavia. |
| 9 September 1004 | Bohemia, Holy Roman Empire [political events] | King Henry II of Germany restores Jaromir as Duke of Bohemia in a war which follows Boleslaw Chrobry (the Brave) of Poland's refusal to pay homage. |
| 9 September 1006 | Flanders, Holy Roman Empire, France [wars] | A joint expedition by King Henry II of Germany and King Robert II of France fails to recover Valenciennes from the expansionist Count Baldwin IV of Flanders, who has also seized the castle of Ghent. |
| 9 September 1087 | England, Normandy [administration] | Following the death of William I the Conqueror, king of England and duke of Normandy, of wounds received suppressing a revolt in the county of Maine, he is succeeded in Normandy by his eldest son, Robert Curthose, who immediately faces a baronial rebellion he is never able to suppress completely. William is succeeded in England by a younger son, William II Rufus. |
| 9 September 1087 | Normandy, England [births and deaths] | William I the Conqueror, duke of Normandy 1035–87, king of England 1066–87, dies in Rouen, Normandy (59). |
| 9 September 1100 | Papal States, Italy [administration] | The antipope Clement III dies; a Roman faction takes advantage of the absence of the legitimate pope Paschal II, currently in southern Italy, to crown Theodoric as Clement's successor, but he is expelled later in the year. |
| 9 September 1106 | Almoravid Emirate, Spain [administration] | Yusuf ibn-Tashfin, the Almoravid emir of Morocco and Muslim Spain, dies; he is succeeded by his son `Ali. |
| 9 September 1112 | France [political events] | A French synod under Archbishop Guido of Vienne declares lay investiture (investiture of senior churchmen by lay rulers) to be heretical and excommunicates Emperor Henry V of Germany. |
| 9 September 1141 | Seljuk Sultanate, Central Asia [wars] | The Seljuk sultan Sanjar is defeated on the Qatwan Steppe, at Samarkand, by the Kara-Khitai Turks who are establishing an empire stretching from China to the River Oxus (present-day Amu Darya) in central Asia. |
| 9 September 1147 | Saxony, Holy Roman Empire, Germany [wars] | The Saxons abandon their crusade against the pagan Wends after failing to take Dobin. |
| 9 September 1168 | Papal States, Italy, Holy Roman Empire [administration] | Abbot John of Struma is elected the successor to the antipope Paschal III, as Calixtus III, and recognized as pope by the Holy Roman Emperor Frederick I Barbarossa. |
| 9 September 1182 | Byzantine Empire [crime and punishment] | Andronicus I Comnenus, nephew of the former emperor John II Comnenus, usurps the throne of the Byzantine Empire, murdering the current emperor Alexius II, his mother, and her advisers. |
| 9 September 1240 | Navarre, Palestine [Crusades (1095–1272)] | King Theobald of Navarre leaves Palestine, ending his crusade. |
| 9 September 1303 | France, Flanders [political events] | King Philip IV of France releases Count Guy of Flanders in an attempt to calm the Flemish uprising, after an unsuccessful French campaign in Flanders. |
| 9 September 1305 | England, Scotland [legislation] | King Edward I of England enacts an ordinance for the government of Scotland. The country is to be ruled by a governor, a lieutenant, and a chamberlain. There is also to be a separate Scottish parliament. |
| 9 September 1499 | Portugal, Africa, Italy [exploration] | Vasco da Gama returns to Lisbon, Portugal, from India, having sailed via Malindi, Kenya, and the Azores in the Atlantic Ocean. The other half of his expeditionary force, which arrived in Lisbon a month earlier, has broken the spice trade monopoly of Venice and the Arabs. |
| 9 September 1513 | England, Scotland [wars] | King Henry VIII of England's northern army under Thomas Howard, Earl of Surrey, annihilates the invading Scottish army at the Battle of Flodden Field, near Branxton, Northumberland. Amongst the more than 10,000 dead is King James IV of Scotland; his infant son succeeds him as James V and the queen, Margaret Tudor, assumes the regency. |
| 9 September 1545 | France [political events] | Charles of Orléans, King Francis I of France's second surviving son, dies, ending the plans for a Habsburg–Valois marriage and consequent French hopes of gaining the Netherlands or Milan in accordance with the 1544 Peace of Crépy. |
| 9 September 1556 | Papal States, Italy, Holy Roman Empire [political events] | Pope Paul IV, claiming the papal veto over the election of the Holy Roman Emperor, refuses to acknowledge Archduke Ferdinand I of Austria, king of the Romans (the German king), Bohemia, and part of Hungary as Holy Roman Emperor Ferdinand I. |
| 9 September 1585 | France [births and deaths] | Armand-Jean du Plessis, Cardinal et duc de Richelieu, (‘Cardinal Richelieu’), chief minister (1624–42) to King Louis XIII of France, who defeated the Habsburg hegemony in Europe, born in Richelieu, Poitou, France (–1642). |
| 9 September 1737 | Papal States [births and deaths] | Luigi Galvani, Italian physician who investigated electrical conduction in living tissues, born in Bologna, Papal States, Italy (–1798). |
| 9 September 1760 | Russia, Sweden, Germany, Holy Roman Empire, Saxony [Seven Years War (1754–62)] | Russian and Swedish troops ravage the Prussian province of Pomerania while imperial troops occupy the German electorate of Saxony and town of Halle. |
| 9 September 1828 | Russia [births and deaths] | Lev Nikolayevich (‘Leo’) Tolstoy, Russian author best known for War and Peace and Anna Karenina, born in Yasnaya Polyana, Russia (–1910). |
| 9 September 1847 | USA [natural resources] | Gold is discovered in California and leads to the first ‘gold rush’. |
| 9 September 1850 | USA [legislation] | The US Congress passes the Texas and New Mexico Act, establishing the boundaries of Texas and New Mexico, and the Utah Act, establishing the boundary of Utah. As part of the so-called Compromise of 1850, the fate of slavery in the prospective states of New Mexico and Utah would be decided by the principal of popular sovereignty. |
| 9 September 1877 | Japan [political events] | The antidemocratic and anti-Western Satsuma Rebellion in Japan ends in defeat for the samurai at Kumamoto. |
| 9 September 1901 | [births and deaths] | Henri de Toulouse-Lautrec, French artist who depicted the personalities of Parisian night life, dies in Malromé, France (36). |
| 9–14 September 1917 | Russian Empire [Russian Revolution] | General Lavr Kornilov attempts a counter-revolutionary coup but is prevented from reaching Petrograd, Russia, by Bolshevik railwaymen. Kornilov is later arrested. |
| 9 September 1932 | Spain [administration] | The northeast region of Catalonia is granted autonomy in Spain, with its own flag, language, and parliament. |
| 9 September 1947 | Argentina [women's rights] | Women in Argentina gain the right to vote thanks to the efforts of First Lady Eva Perón. |
| 9 September 1948 | North Korea, South Korea [political events] | The Supreme People's Assembly in North Korea proclaims the Democratic People's Republic of Korea, with Pyongyang as its capital, and claims authority over the entire country of Korea. The prime minister is Kim Il Sung. |
| 9 September 1960 | Iran, Iraq, Saudi Arabia, Kuwait, Venezuela [international organizations] | Representatives of Iran, Iraq, Kuwait, Saudi Arabia, and Venezuela meet in Baghdad, Iraq, and vote to establish the Organization of Petroleum-Exporting Countries (OPEC), a permanent organization to represent their interests. OPEC is finally formed in 1961. |
| 9 September 1960 | USA [American football] | A crowd of 21,597 watches the Denver Broncos defeat the Boston Patriots 13–10 in Boston, Massachusetts, in the first American Football League (AFL) regular season game. The AFL was formed earlier this year as a rival to the National Football League (NFL). |
| 9 September 1970 | UK [sex and sexuality] | Ann Summers launches her chain of sex shops with the opening of the Ann Summers Sex Supermarket in London, England. |
| 9 September 1976 | China [births and deaths] | Mao Zedong, Chinese Marxist theorist who was chair of the People's Republic of China 1949–59 and chair of the Chinese Communist Party 1949–76, dies in Beijing, China (83). |
| 9 September 1993 | Somalia, USA [political events] | Two hundred civilians are killed when a US helicopter on United Nations (UN) peacekeeping duty fires on a crowd in Mogadishu, Somalia. |
| 9 September 2007 | Italy [athletics] | Jamaican sprinter Asafa Powell breaks his own world record for the 100 metres by running 9.74 seconds at an athletics competition in Italy. |