18th day events in history

September 18, 14 Tiberius is confirmed as Roman emperor by the Roman Senate following the natural death of Augustus
March 18, 37 The Roman Senate annuls Tiberius's will and proclaims Caligula emperor
September 18, 96 Nerva is proclaimed Roman emperor after Domitian is assassinated
March 18, 235 Emperor Alexander Severus and his mother Julia Mamaea are murdered by legionaries near Mogontiacum (modern Mainz), ending the Severan dynasty
October 18, 320 Pappus of Alexandria, Greek philosopher, observes an eclipse of the Sun and writes a commentary on The Great Astronomer (Almagest)
September 18, 324 Constantine the Great decisively defeats Licinius in the Battle of Chrysopolis, establishing Constantine's sole control over the Roman Empire
November 18, 326 The old St. Peter's Basilica is consecrated
May 18, 332 Constantine the Great announced free distributions of food to the citizens in Constantinople
January 18, 350 General Magnentius deposes Roman Emperor Constans and proclaims himself Emperor
July 18, 362 Roman–Persian Wars: Emperor Julian arrives at Antioch with a Roman expeditionary force (60,000 men) and stays there for nine months to launch a campaign against the Persian Empire
November 18, 401 The Visigoths, led by king Alaric I, cross the Alps and invade northern Italy
January 18, 474 Seven-year-old Leo II succeeds his maternal grandfather Leo I as Byzantine emperor. He dies ten months later
January 18, 532 Nika riots in Constantinople fail
October 18, 614 King Chlothar II promulgates the Edict of Paris (Edictum Chlotacharii), a sort of Frankish Magna Carta that defend the rights of the Frankish nobles while it excludes Jews from all civil employment in the Frankish Kingdom
June 18, 618 Li Yuan becomes Emperor Gaozu of Tang, initiating three centuries of Tang Dynasty rule over China
October 18, 629 Dagobert I is crowned King of the Franks
March 18, 633 Ridda Wars: The Arabian Peninsula is united under the central authority of Caliph Abu Bakr
July 18, 645 Chinese forces under general Li Shiji besiege the strategic fortress city of Anshi (Liaoning) during the Goguryeo–Tang War
August 18, 684 Battle of Marj Rahit: Umayyad partisans defeat the supporters of Ibn al-Zubayr and cement Umayyad control of Syria
October 18, 1009 The Church of the Holy Sepulchre, a Christian church in Jerusalem, is completely destroyed by the Fatimid caliph Al-Hakim bi-Amr Allah, who hacks the Church's foundations down to bedrock
October 18, 1016 The Danes defeat the Saxons in the Battle of Assandun
April 18, 1025 Bolesław Chrobry is crowned in Gniezno, becoming the first King of Poland
June 18, 1053 Battle of Civitate: Three thousand horsemen of Norman Count Humphrey rout the troops of Pope Leo IX
October 18, 1081 The Normans defeat the Byzantine Empire in the Battle of Dyrrhachium
May 18, 1096 First Crusade: around 800 Jews are massacred in Worms, Germany
November 18, 1105 Maginulfo is elected the Antipope as Sylvester IV
January 18, 1126 Emperor Huizong abdicates the Chinese throne in favour of his son Emperor Qinzong
May 18, 1152 Henry II of England marries Eleanor of Aquitaine
June 18, 1178 Five Canterbury monks see what is possibly the Giordano Bruno crater being formed. It is believed that the current oscillations of the Moon's distance from the Earth (on the order of meters) are a result of this collision
September 18, 1180 Philip Augustus becomes king of France
November 18, 1180 Phillip II becomes king of France
October 18, 1210 Pope Innocent III excommunicates Otto IV, Holy Roman Emperor
November 18, 1210 Pope Innocent III excommunicates Holy Roman Emperor Otto IV
February 18, 1229 The Sixth Crusade: Frederick II, Holy Roman Emperor signs a ten-year truce with al-Kamil, regaining Jerusalem, Nazareth, and Bethlehem with neither military engagements nor support from the papacy
March 18, 1229 Frederick II, Holy Roman Emperor, declares himself King of Jerusalem in the Sixth Crusade
March 18, 1241 First Mongol invasion of Poland: Mongols overwhelm Polish armies in Kraków in the Battle of Chmielnik and plunder the city
June 18, 1264 The Parliament of Ireland meets at Castledermot in County Kildare, the first definitively known meeting of this Irish legislature
February 18, 1268 The Livonian Brothers of the Sword are defeated by Dovmont of Pskov in the Battle of Rakvere
May 18, 1268 The Principality of Antioch, a crusader state, falls to the Mamluk Sultan Baibars in the Siege of Antioch
December 18, 1271 Kublai Khan renames his empire "Yuan" (元 yuán), officially marking the start of the Yuan Dynasty of Mongolia and China
July 18, 1290 King Edward I of England issues the Edict of Expulsion, banishing all Jews (numbering about 16,000) from England; this was Tisha B'Av on the Hebrew calendar, a day that commemorates many Jewish calamities
May 18, 1302 Bruges Matins, the nocturnal massacre of the French garrison in Bruges by members of the local Flemish militia
November 18, 1302 Pope Boniface VIII issues the Papal bull Unam sanctam (One Faith)
August 18, 1304 The Battle of Mons-en-Pévèle is fought to a draw between the French army and the Flemish militias
November 18, 1307 William Tell shoots an apple off his son's head
March 18, 1314 Jacques de Molay, the 23rd and the last Grand Master of the Knights Templar, is burned at the stake
February 18, 1332 Amda Seyon I, Emperor of Ethiopia begins his campaigns in the southern Muslim provinces
July 18, 1334 The bishop of Florence blesses the first foundation stone for the new campanile (bell tower) of the Florence Cathedral, designed by the artist Giotto di Bondone
July 18, 1342 Mu'izz al-Din Husayn defeats the Sarbadars in the Battle of Zava
October 18, 1356 Basel earthquake, the most significant historic seismological event north of the Alps, destroys the town of Basel, Switzerland