Browse Historical Events by Month: What Happened in May?

A solar eclipse occurred during a battle between the Lydians and the Medes in what is now Turkey. It is one of the earliest recorded events in history.

The temple of the Roman god Mercury was dedicated on the Aventine Hill in Rome. This temple was a significant site for the worship of Mercury, who was the Roman god of commerce.

The Peloponnesian War begins between Athens and Sparta, marking the start of a decades-long conflict in Ancient Greece.

The ancient city of Byzantium was selected to serve as the new capital of the Roman Empire, and the city was renamed Nova Roma, or 'New Rome', by Emperor Constantine the Great.

First Council of Nicaea - the first ecumenical council of Christian bishops at Nicaea, Asia Minor.

Athanasius is unanimously elected to be Bishop Patriarch of Alexandria after the death of Alexander. Athanasius was believed to be about 30 years old at the time. 

Byzantium was renamed Constantinople (now Istanbul) and dedicated to Emperor Constantine. Constantinople is generally considered to be the center and the "cradle of Orthodox Christian civilization". Constantinople was the largest and wealthiest city in Europe, from the mid-5th century to the early 13th century.

Roman Emperor Constantine I, (Constantine the Great), was baptized in Nicomedia. Constantine  had favored Christianity for most of his life and played a significant role in its legalization and spread,. He was baptized  shortly before his death by Eusebius of Nicomedia, an Arian bishop, though some Catholic and Coptic Orthodox traditions claim he was baptized by Pope Sylvester I.

Gregory V becomes Pope of the Roman Catholic Church after being appointed by his cousin, Holy Roman Emperor Otto III. Born as Bruno of Carinthia, he was the first German-born pope and served as the ruler of the Papal States until his death in 999. Gregory's pontificate was turbulent, marked by a rebellion in Rome and his efforts to restore his cousin to the imperial throne.

Holy Roman Emperor Frederick I Barbarossa and 100,000 crusaders depart Regensburg for the Third Crusade which is also known as the Kings's Crusade. It was an attempt led by three European monarchs of Western Christianity (Philip II of France, Richard I of England and Frederick I, Holy Roman Emperor) to reconquer the Holy Land following the capture of Jerusalem by the Ayyubid sultan Saladin in 1187. 

Baldwin I of Flanders is crowned the first Latin Emperor of Constantinople during the Fourth Crusade.

The Augustinian monastic order is constituted at the Lecceto Monastery when Pope Alexander IV issues papal bull Licet ecclesiae catholicae More

Beginning of the Hundred Years' War - King Edward III of England formally declares war against King Philip VI of France, marking the start of a long-lasting conflict between the two kingdoms which is referred to as the Hundred Years' War which was eventually won by the French at the Battle of Castillon in 1453. This was largely due to the French use of guns against the English.

Siege of Calais begins: King Edward III of England surrounds the city of Calais during the Hundred Years' War, leading to a prolonged siege lasting over a year.

The Treaty of Brétigny is signed, ending the first phase of the Hundred Years' War between England and France and granting significant territorial concessions to England. 8 May 1360

The Treaty of Brétigny is signed between England and France, marking a temporary end to the first phase of the Hundred Years' War and granting substantial territorial concessions to England.

Peasants' Revolt in England: The Peasants' Revolt, a major uprising against high taxes and social injustice, culminates in a confrontation between rebel forces and King Richard II at Smithfield in London.

The Battle of Beverhoutsveld takes place between Louis II, Count of Flanders, leading the forces of the town of Brugesakes, against the Ghent forces led by Philip van Artevelde. The battle takes place near Bruges in modern-day Belgium, on a field located between the towns of Beernem, Oostkamp and Assebroek, resulting on the defeat of the Count of Flanders. The Ghent forces occupied the town of Bruges that same day but the Count Louis II managed to escape and fled to the town of Rijssel. The Battle of Beverhoutsveld  marked an important phase in the rebellion of Ghent. More

Joan of Arc is captured by the Burgundians and sold to the English, leading to her trial and execution.

Joan of Arc, the peasant girl daughter of a tenant farmer at Domremy, who led the French army to victory over England at Orleans during the Hundred Years' War, was burned at the stake for heresy by an English-dominated tribunal in Rouen. More