| 5 May 431 BC | Greece [Peloponnesian War (431 BC)] | The Spartans invade Attica, marking the start of the 27-year Peloponnesian War. The Athenian army is outclassed by the Spartans and Athens' power lies in its navy, so the Athenian statesman Pericles brings the population of the country districts into the city of Athens while pursuing an active naval war. Athens insures itself against danger from the island of Aegina by supplanting its Doric population with Athenians. |
| 5 May 878 | Wessex, Denmark [wars] | King Alfred the Great of Wessex, England, defeats the Danes at Edington (in Wiltshire). By the Peace of Wedmore which follows, the Danish leader, Guthrum, is baptized as a Christian. |
| 5 May 928 | Italy [administration] | Pope John X is deposed and murdered. He is succeeded by Leo VI, who dies before the year is out and is replaced by another puppet pope, Stephen VII, who is completely dominated by the aristocracy of Rome. |
| 5 May 1063 | England, Wales [wars] | Harold Godwinson, Earl of Wessex, begins a campaign against King Gruffydd ap Llywelyn of Wales. |
| 5 May 1084 | Holy Roman Empire, Papal States, Apulia, Italy [wars] | Answering a call for help from Pope Gregory VII, Robert Guiscard, the Norman duke of Apulia, expels the Germans from Rome; however, the Norman soldiers do so much damage that Gregory is forced to go into exile with them to escape popular anger. |
| 5 May 1138 | England [wars] | Robert, Earl of Gloucester, begins a civil war in England by declaring himself for the late King Henry I's daughter Matilda against King Stephen. |
| 5 May 1142 | Germany, Saxony, Bavaria, Holy Roman Empire [administration] | The civil war in Germany is brought to an end by a diet (legislative assembly) in Frankfurt; Conrad III Hohenstaufen, king of the Germans, grants Saxony to Henry the Lion and Bavaria to Henry Jasomirgott, brother of Leopold IV of Austria. |
| 5 May 1224 | France, England [wars] | King Louis VIII of France declares war on King Henry III of England; he then overruns Poitou and most of Gascony north of the River Garonne. |
| 5 May 1297 | Scotland, England [Anglo–Scottish Wars 1296–1371)] | The Scottish nationalist William Wallace leads a Scottish rising against King Edward I of England, burning an English castle and attacking one of the king's justiciars. |
| 5 May 1299 | Genoa, Venice [wars] | Matteo Visconti negotiates a peace between Genoa and Venice, ending their war (since 1261) to control trade with the Byzantine Empire. |
| 5 May 1300 | Flanders, France [political events] | Guy of Flanders, having been deserted by all his allies, surrenders to King Philip IV of France and is imprisoned. Flanders is placed under French governance, and is adminstered by Jacques de Châtillon, the uncle of the queen. |
| 5 May 1318 | Scotland, England [Anglo–Scottish Wars 1296–1371)] | Robert I the Bruce, King of Scotland, raids as far as Ripon in England, exacting tribute. |
| 5 May 1506 | France, Holy Roman Empire [political events] | Revoking the Treaty of Blois of 1504, King Louis XII of France breaks the engagement of his daughter Claude to Archduke Charles (the future Holy Roman Emperor Charles V), son of Philip (‘the Handsome’), Duke of Burgundy. The Estates General (parliament) of France has declared that the duchies of Brittany and Burgundy and the county of Blois are inalienable. Claude is betrothed instead to Louis's cousin and heir presumptive, Francis of Angoulême, Duke of Valois, the future King Francis I. |
| 5 May 1646 | UK [British Civil Wars (1642–51)] | Having left Oxford in disguise on 27 April, following Parliament's success in mopping up the final Royalist pockets of resistance in England, King Charles I surrenders to the Scots at Southwall, near Newark, Nottinghamshire. |
| 5 May 1705 | Austria, Habsburg Monarchy, Holy Roman Empire [political events] | Following the death of the Holy Roman Emperor, Leopold I of Austria, he is succeeded by his son Joseph I. |
| 5 May 1744 | Prussia, Bavaria, Germany, Palatinate, Austria, Holy Roman Empire, Habsburg Monarchy [diplomacy] | The Union of Frankfurt is agreed between King Frederick II (the Great) of Prussia, Holy Roman Emperor Charles VII (Charles Albert of Bavaria), the Elector Palatine, and the Landgrave of Hesse, to force Maria Theresa of Austria to restore Bavaria, make peace, and restore the constitution of the Holy Roman Empire. |
| 5 May 1762 | Russia, Prussia [treaties] | Tsar Peter III, an admirer of Frederick II the Great of Prussia, ends hostilities between Russia and Prussia, by the Treaty of St Petersburg. Russia restores all conquests made during the Seven Years' War and agrees to a military alliance with Prussia. |
| 5 May 1818 | Prussia [births and deaths] | Karl Marx, Prussian political theorist, economist, and sociologist whose ideas formed the basis of communism, born in Trier, Prussia (–1883). |
| 5 May 1821 | France [births and deaths] | Napoleon I (Napoleon Bonaparte), French general, First Consul 1799–1804, and emperor of France 1804–15, dies in exile on the island of St Helena in the South Atlantic (52). |
| 5 May 1860 | Italy [political events] | The Italian soldier and patriot Giuseppe Garibaldi and his Redshirts (‘The Thousand’) sail from Genoa, northwest Italy, to attempt to complete the unification of Italy. |
| 5–6 May 1864 | USA [American Civil War (1861–65)] | The Union under General Ulysses S Grant and the Confederates under General Robert E Lee fight the indecisive Battle of the Wilderness, Virginia. |
| 5 May 1881 | France [biology] | French microbiologist Louis Pasteur vaccinates sheep against anthrax. It is the first infectious disease to be treated effectively with an antibacterial vaccine, and his success lays the foundations of immunology. |
| 5 May–27 June 1893 | USA [economic conditions] | Panic grips Wall Street as the stock prices dive in the USA. By the end of June, some 600 banks and 15,000 businesses have closed and 74 railways have declared bankruptcy. |
| 5 May 1894 | USA [legislation] | US president Grover Cleveland repeals the McKinley Tariff of October 1890. |
| 5 May 1920 | Latvia, Germany [treaties] | The Treaty of Berlin ends the war between Germany and Latvia and recognizes Latvian independence. |
| 5 May 1921 | France [clothing and fashion] | Chanel No. 5 perfume, created by perfumer Ernst Beaux, is launched. |
| 5 May 1946 | Greece [wars] | Civil war breaks out in Greece between the British-backed monarchists and the communists supported by Albania, Bulgaria, and Yugoslavia. |
| 5 May 1947 | Japan [women's rights] | The Japanese parliament adopts an equal-rights amendment that bans discrimination by sex and gives women the power to bring lawsuits charging bias. |
| 5 May 1961 | USA [space exploration] | US astronaut Alan Shepard in the Mercury capsule Freedom 7 makes a 14.8-minute single sub-orbital flight. He is the first US astronaut in space. |
| 5 May 1980 | UK, Iran [political events] | Britain's Special Air Service (SAS) storms the Iranian embassy in London, England, retaking it from the terrorists who seized the building on 30 April. |
| 5 May 1981 | Northern Ireland [political events] | Riots break out in Northern Ireland following the death of the Irish Republican Army (IRA) hunger striker and successful parliamentary candidate Bobby Sands in the Maze prison. |
| 5 May 1988 | USA [Catholicism] | Eugene Antonio Marino is installed as archbishop of Atlanta, the first black Roman Catholic archbishop in the USA. |
| 5 May 2000 | Sierra Leone [United Nations] | Revolutionary United Front rebels in Sierra Leone take UN peacekeepers hostage in their campaign against the government. They seize 208 Zambian peacekeepers, bringing the total number of UN hostages to 318. |
