September 11145 – The main altar of Lund Cathedral, at the time seat of the archiepiscopal see of all the Nordic countries, is consecrated. 1173 – The widow Stamira sacrifices herself in order to raise the siege of Ancona by the forces of Emperor Frederick Barbarossa. 1355 – King Tvrtko I of Bosnia writes In castro nostro Vizoka vocatum from the Old town of Visoki. 1449 – Tumu Crisis: The Mongols capture the Emperor of China. 1529 – The Spanish fort of Sancti Spiritu, the first one built in modern Argentina, is destroyed by indigenous people.
May 2617 – Germanicus celebrates a triumph in Rome for his victories over the Cherusci, Chatti, and other German tribes west of the Elbe. 451 – Battle of Avarayr between Armenian rebels and the Sasanian Empire takes place. The Sasanids defeat the Armenians militarily but guarantee them freedom to openly practice Christianity. 946 – King Edmund I of England is murdered by a thief whom he personally attacks while celebrating St Augustine's Mass Day. 961 – King Otto I elects his six-year-old son Otto II as heir apparent and co-ruler of the East Frankish Kingdom.
February 8421 – Constantius III becomes co-Emperor of the Western Roman Empire. 1238 – The Mongols burn the Russian city of Vladimir. 1250 – Seventh Crusade: Crusaders engage Ayyubid forces in the Battle of Al Mansurah. 1347 – The Byzantine civil war of 1341–47 ends with a power-sharing agreement between John VI Kantakouzenos and John V Palaiologos. 1575 – Leiden University is founded, and given the motto Praesidium Libertatis. 1587 – Mary, Queen of Scots, is executed on suspicion of having been involved in the Babington Plot to murder her cousin, Queen Elizabeth I.
February 121096 – Pope Urban II confirms the foundation of the abbey of La Roë under Robert of Arbrissel as a community of canons regular. 1404 – The Italian professor Galeazzo di Santa Sophie performed the first post-mortem autopsy for the purposes of teaching and demonstration at the Heiligen–Geist Spital in Vienna. 1429 – English forces under Sir John Fastolf defend a supply convoy carrying rations to the army besieging Orléans in the Battle of the Herrings.
March 15474 BC – Roman consul Aulus Manlius Vulso celebrates an ovation for concluding the war against Veii and securing a forty years truce. 44 BC – The assassination of Julius Caesar takes place on the Ides of March. 493 – Odoacer, the first barbarian King of Italy after the fall of the Western Roman Empire, is slain by Theoderic the Great, king of the Ostrogoths, while the two kings were feasting together. 856 – Michael III, emperor of the Byzantine Empire, overthrows the regency of his mother, empress Theodora (wife of Theophilos) with support of the Byzantine nobility.
January 18474 – Seven-year-old Leo II succeeds his maternal grandfather Leo I as Byzantine emperor. He dies ten months later. 532 – Nika riots in Constantinople fail. 1126 – Emperor Huizong abdicates the Chinese throne in favour of his son Emperor Qinzong. 1486 – King Henry VII of England marries Elizabeth of York, daughter of Edward IV, uniting the House of Lancaster and the House of York. 1562 – Pope Pius IV reopens the Council of Trent for its third and final session. 1586 – The magnitude 7.
March 1837 – Roman Senate annuls Tiberius' will and proclaims Gaius Julius Caesar Augustus Germanicus (aka Caligula = Little Boots) emperor. 1068 – An earthquake in the Levant and the Arabian Peninsula leaves up to 20,000 dead. 1229 – Frederick II, Holy Roman Emperor, declares himself King of Jerusalem in the Sixth Crusade. 1241 – First Mongol invasion of Poland: Mongols overwhelm Polish armies in Kraków in the Battle of Chmielnik and plunder the city. 1314 – Jacques de Molay, the 23rd and final Grand Master of the Knights Templar, is burned at the stake.
August 19295 BC – The first temple to Venus, the Roman goddess of love, beauty and fertility, is dedicated by Quintus Fabius Maximus Gurges during the Third Samnite War. 43 BC – Gaius Julius Caesar Octavianus, later known as Augustus, compels the Roman Senate to elect him Consul. 947 – Abu Yazid, a Kharijite rebel leader, is defeated and killed in the Hodna Mountains in modern-day Algeria by Fatimid forces. 1153 – Baldwin III of Jerusalem takes control of the Kingdom of Jerusalem from his mother Melisende, and also captures Ascalon.
January 2798 – Trajan succeeds his adoptive father Nerva as Roman emperor; under his rule the Roman Empire will reach its maximum extent. 945 – The co-emperors Stephen and Constantine are overthrown and forced to become monks by Constantine VII, who becomes sole emperor of the Byzantine Empire. 1186 – Henry VI, the son and heir of the Holy Roman Emperor Frederick I, marries Constance of Sicily. 1302 – Dante Alighieri is condemned in absentia and exiled from Florence.
March 1509 BC – Publius Valerius Publicola celebrates the first triumph of the Roman Republic after his victory over the deposed king Lucius Tarquinius Superbus at the Battle of Silva Arsia. 293 – Emperor Diocletian and Maximian appoint Constantius Chlorus and Galerius as Caesars. This is considered the beginning of the Tetrarchy, known as the Quattuor Principes Mundi ("Four Rulers of the World"). 350 – Vetranio proclaims himself Caesar after being encouraged to do so by Constantina, sister of Constantius II.