6 June

6 June 390 BC	Rome [wars]	A wandering tribe of Celts (whom the Romans call Gauls) defeats the Romans, deserted by their allies, at the Battle of the Allia and Rome is besieged for six months until only the Capitol is unconquered. The rest of the city is sacked by the Gauls. They are probably bought off with gold, though the legend grows that the former Roman dictator Camillus is recalled from exile and defeats them.
6 June 53 BC	Rome, Parthia [Roman–Parthian War (39 BC)]	The Roman general and statesman Marcus Crassus rashly penetrates into the Mesopotamian desert, which results in the defeat of his army by the Parthians (led by their Arsacian king, Orodes II) at the Battle of Carrhae.
6 June 913	Byzantine Empire [political events]	Shortly after provoking a war with the Bulgars, the Byzantine emperor, Alexander, dies leaving the empire in the hands of his seven-year-old nephew Constantine VII (the son of the former emperor Leo VI).
6 June 1222	Mongol Empire, Khwarizm [Mongol conquests (1206–1405)]	The Mongol leader Genghis Khan takes the city of Herat and massacres its population, completing his conquest of the Khwarizm shahdom (modern Iran, Afghanistan, and part of Central Asia).
6 June 1305	France, Flanders [treaties]	In the Treaty of Athis-sur-Orge, King Philip IV of France restores Flanders to Robert of Béthune for the payment of an indemnity.
6 June 1473	Japan [wars]	In Japan, Hosokawa Katsumoto, leader of the loyalist faction in the Onin War, dies. Following the earlier death of his opponent Yamana Mochitoyo, this ends any prospect of a truce and many residents leave the devastated capital, Kyoto, as Japan descends into feudal chaos.
6 June 1557	Portugal [political events]	Sebastian I, aged three, succeeds as king of Portugal on the death of his grandfather King John III; Sebastian's mother, Joanna of Austria, daughter of the former Holy Roman Emperor Charles V, acts as regent until 1562.
6 June 1660	Sweden, Denmark-Norway [treaties]	The Peace of Copenhagen formally ends the second war between Sweden and Denmark. Denmark's loss of lands in southern Sweden is confirmed and the Concert of The Hague successfully negotiates for the Baltic to be reopened to foreign ships.
6 June 1690	Spain, Holy Roman Empire, United Netherlands, UK [diplomacy]	Spain joins the Holy Roman Emperor Leopold I, the United Netherlands, and Britain in the Grand Alliance against France.
6 June–7 July 1718	Spain, Sicily [wars]	A Spanish army sails for Sicily. The property of the Spanish crown since the 16th century, Sicily had been given to the Duke of Savoy, under the terms of the Treaty of Utrecht, in return for his services in the Allied cause during the War of the Spanish Succession. The Spanish government hopes to use Sicily as a base for the invasion of Italy, and its troops conquer the island by July.
6 June 1797	Genoa [political events]	Napoleon Bonaparte establishes the French-dominated Ligurian Republic in Genoa, Italy.
6 June 1801	Spain, Portugal, UK [treaties]	The Treaty of Badajoz formally ends the war between Spain and Portugal over Portugal's traditional allegiance to Britain. Portugal cedes the province of Olivenza and agrees to close its ports to British ships.
6 June 1820	UK [political events]	Caroline, Princess of Wales, whom King George IV of Britain wishes to divorce, triumphantly enters London, England, demanding her recognition as queen.
6 June 1837	Natal [colonization]	The Republic of Natal is formally established by Dutch settlers in southern Africa and a constitution is proclaimed.
6 June 1846	USA [religious freedom]	Mormon Church leader Brigham Young, who replaced the murdered Joseph Smith, leads his followers out of Nauvoo, Illinois, to escape persecution. They set out for the Great Salt Lake in Utah in what becomes known as the Mormon migration.
6 June 1880	Belgium [elections]	The Clericals defeat their ideological rivals, the Liberals, in the Belgian elections and begin a long era of power which extends until 1914.
6 June 1892	Japan [administration]	The pro-Western Prince Hirobumi Ito becomes premier of Japan.
6 June 1906	Russian Empire [law and government]	The reformer Peter Stolypin becomes prime minister of Russia.
6 June 1907	Germany [everyday life]	British chemical company Lever Bros launches Persil, the first ever household detergent, in Germany.
6 June 1916	Greece [World War I (1914–18)]	British and French armies blockade Greece, suspecting that King Constantine is in league with the Central Powers, and only relent when the Greek army is stood down on 22 June.
6 June 1927	Syria, France [political events]	The Druze revolt against French rule in Syria is finally ended.
6 June 1933	Germany [cinema and film]	Josef Goebbels, the German Minister of Information and Propaganda, authorizes legislation to exclude Jews and foreigners from involvement in film production. As the Nazis increase their control over the cinema industry, a number of noted Germans involved in film production, notably Fritz Lang, Erich Pommer, Leontine Sagan, and Max Ophüls, leave the country.
6 June 1934	USA [legislation]	The US Congress passes the Reciprocal Trade Agreement Act. It authorizes the president to conclude trade agreements with individual nations, thereby annulling the 1930 Smoot–Hawley tariff.
6 June 1944	France, UK, USA, Canada, Germany [World War II (1939–45)]	D-day marks the start of Operation Overlord. Allied forces (British, US, and Canadian) land on five beaches in Normandy, northwest France, against heavy German opposition.
6 June 1960	USA [health and medicine]	A study by the American Heart Association finds that men who smoke are 50–150% more likely to die from coronary disease than nonsmokers.
6 June 1961	Switzerland [births and deaths]	Carl Jung, Swiss psychologist who founded analytic psychology, dies in Küsnacht, Switzerland (85).
6 June 1999	Federal Republic of Yugoslavia [Balkan conflicts (c. 1991–2000)]	Peace talks between Yugoslav and NATO military leaders are deadlocked when the Yugloslavs reject terms of a seven-day withdrawal out of Kosovo. NATO continues its bombing campaign, insisting it will not stop until Yugoslav president Slobodan Miloševic agrees to NATO's terms.

June 6

6 June