September 09

Events

337day.year

Constantine II, Constantius II, and Constans succeed their father Constantine I as co-emperors. The Roman Empire is divided between the three Augusti.

After the death of Constantine I, his three sons—Constantine II, Constantius II, and Constans—become co-emperors, dividing the Roman Empire among them.
In 337 AD, Emperor Constantine I passed away, leading to the elevation of his three sons to the imperial office. Constantine II took control of the western provinces, Constans ruled the central regions, and Constantius II governed the eastern territories. This tripartite arrangement marked the first time the empire was formally partitioned among Augusti. The decision aimed to stabilize governance but also sowed seeds of rivalry. Each brother now held supreme authority in his domain, with distinct military and administrative hierarchies. The division reflected both Constantine I’s legacy and the complexities of dynastic rule. It set a precedent for the power-sharing experiments that would recur in later Roman history.
337 Constantine II Constantius II Constans Constantine I Roman Empire Augusti
1000day.year

Battle of Svolder, Viking Age.

The Battle of Svolder, fought in 1000 AD, saw King Olaf Tryggvason of Norway ambushed and defeated by a coalition of rival Scandinavian rulers.
In the autumn of 1000, the Battle of Svolder took place in the western Baltic Sea near an island called Svolder. King Olaf Tryggvason of Norway, returning from a pilgrimage, was lured into a trap by allied forces led by King Sweyn Forkbeard of Denmark, King Olof Skötkonung of Sweden, and Earl Eirik of Lade. Outnumbered and outmaneuvered, Olaf’s fleet suffered heavy losses. According to saga accounts, the king fought bravely before his ship was overwhelmed. His mysterious disappearance sparked legends of his fate. The battle shifted the balance of power in Scandinavia and led to a period of Danish and Swedish influence over Norway. Svolder remains one of the most famous naval engagements of the Viking Age.
1000 Battle of Svolder Viking Age
1141day.year

Yelü Dashi, the Liao dynasty general who founded the Qara Khitai, defeats the Seljuq and Kara-Khanid forces at the Battle of Qatwan.

Yelü Dashi, founder of the Qara Khitai, dealt a crushing blow to the Seljuq and Kara-Khanid armies at the Battle of Qatwan in 1141.
In 1141, near the Qatwan Plain in present-day Kyrgyzstan, Liao dynasty general Yelü Dashi led the forces of the newly established Qara Khitai against a combined Seljuq and Kara-Khanid army. Despite being outnumbered, Yelü employed superior tactics and discipline to encircle and rout the enemy cavalry. The victory at Qatwan confirmed the Qara Khitai as a major power in Central Asia. It disrupted Seljuq control over the region and opened new routes for trade and cultural exchange. Yelü Dashi’s triumph also secured his position as the first emperor of the Western Liao dynasty. The battle underscored the importance of steppe warfare innovations and marked a turning point in medieval Central Asian politics. Its outcome influenced power dynamics along the Silk Road for decades.
1141 Yelü Dashi Liao dynasty Qara Khitai Seljuq Kara-Khanid Battle of Qatwan
1320day.year

In the Battle of Saint George, the Byzantines under Andronikos Asen ambush and defeat the forces of the Principality of Achaea, securing possession of Arcadia.

Byzantine forces under Andronikos Asen ambushed and defeated the Principality of Achaea at the Battle of Saint George in 1320, reclaiming Arcadia.
On September 9, 1320, Byzantine commander Andronikos Asen orchestrated a surprise attack against the Principality of Achaea’s army in the Peloponnese region of Greece. Utilizing local knowledge and covert movements, his troops caught their opponents off guard near a hill known as Saint George. The Achaean forces, unprepared for the ambush, quickly fell into disarray. The victory restored Byzantine authority over the strategic territory of Arcadia. It also boosted morale within the empire and weakened Frankish influence in the region. Andronikos Asen’s leadership and use of guerrilla tactics became celebrated in contemporary chronicles. The battle demonstrated the resilience of Byzantine military tradition during a period of fragmentation. Its success paved the way for further reconquest efforts in the Morea.
1320 Battle of Saint George Byzantines Andronikos Asen Principality of Achaea Arcadia
1488day.year

Anne becomes sovereign Duchess of Brittany, becoming a central figure in the struggle for influence that leads to the union of Brittany and France.

Anne of Brittany ascends as the sovereign Duchess in 1488, playing a key role in Brittany’s eventual union with France.
In 1488, following the death of her father Francis II, Anne of Brittany, at thirteen years old, inherited the ducal crown and became Duchess of Brittany. Her accession triggered a power struggle between the duchy and the French crown, as King Charles VIII sought to assert his influence. Anne’s marriage negotiations became central to diplomatic efforts, with both France and England vying for her hand. Her eventual union with Charles VIII in 1491 led to the formal integration of Brittany into the French kingdom. Throughout her reign, Anne worked to preserve Breton autonomy and culture, commissioning illuminated manuscripts and supporting local institutions. She was known for her political acumen and patronage of the arts. Anne’s tenure as duchess laid the groundwork for the modern borders of France and the decline of independent Breton rule.
1488 Anne Duchess of Brittany union of Brittany and France
1493day.year

Battle of Krbava Field, a decisive defeat of Croats in Croatian struggle against the invasion by the Ottoman Empire.

At the Battle of Krbava Field in 1493, Ottoman forces achieved a decisive victory over Croatian defenders, impacting the region’s resistance to Ottoman expansion.
On September 9, 1493, near Udbina in present-day Croatia, Croatian nobility assembled an army to confront the advancing Ottoman forces. The skirmish culminated in the Battle of Krbava Field, where superior Ottoman tactics and cavalry overwhelmed the Croatian troops. The defeat resulted in heavy casualties and the loss of many noble families. The catastrophic outcome weakened Croatia’s military capacity and accelerated Ottoman incursions into the Balkans. Survivors’ accounts describe the chaos and the scale of the slaughter on the open plains. The battle’s legacy endured in Croatian collective memory as a symbol of resistance and suffering. It also prompted reforms in regional defense and fortification strategies. Krbava Field marked a turning point in the Croatian-Ottoman conflicts of the late 15th century.
1493 Battle of Krbava Field Croats Croatian Ottoman Empire
1493day.year

Christopher Columbus, with 17 ships and 1,200 men, sails on second voyage from Cadiz.

Christopher Columbus sets sail from Cádiz on his second voyage in 1493, leading a larger fleet and crew for further exploration of the West Indies.
On September 9, 1493, Christopher Columbus departed Cádiz with a fleet of 17 ships and approximately 1,200 men bound for the New World. Unlike his first voyage, this expedition aimed to establish permanent settlements and assert Spanish sovereignty over newly discovered lands. Columbus’s ships carried settlers, livestock, and supplies for colonization efforts in the Caribbean. The journey reflected Spain’s growing ambitions in global exploration and competition with other European powers. During the voyage, the fleet charted several islands in the Lesser Antilles, including Dominica and Guadeloupe. Columbus imposed his governance structure and sent ships back to Spain with reports and treasures. Despite internal dissent and logistical challenges, this expedition laid the foundations for Spain’s colonial empire in the Americas. The second voyage also intensified encounters between Europeans and indigenous peoples, shaping future colonial policies.
Christopher Columbus
1499day.year

The citizens of Lisbon celebrate the triumphal return of the explorer Vasco de Gama, completing his two-year journey around the Cape of Good Hope to India.

After a two-year expedition around the Cape of Good Hope, Vasco da Gama returns to Lisbon in 1499, heralding a new era of maritime trade with India.
On September 9, 1499, Vasco da Gama arrived in Lisbon to immense public celebration following his pioneering voyage to India. His ships had navigated around Africa’s Cape of Good Hope, opening a direct sea route between Europe and Asia. The expedition brought back spices, silks, and exotic goods that promised enormous profits for Portuguese merchants. Da Gama’s journey marked the culmination of Portugal’s decade-long search for an all-water passage to the riches of the East. The success of the voyage shifted commercial power in Europe and challenged overland trade routes controlled by Middle Eastern intermediaries. King Manuel I rewarded da Gama and invested heavily in the new maritime empire. News of the achievement spread across Europe, igniting further expeditions by rival nations. The return of da Gama’s fleet transformed global trade and heralded the Age of Discovery.
1499 Vasco de Gama Cape of Good Hope
1513day.year

James IV of Scotland is defeated and dies in the Battle of Flodden, ending Scotland's involvement in the War of the League of Cambrai.

King James IV of Scotland is killed at the Battle of Flodden in 1513, delivering a crushing defeat to Scottish forces against England.
On September 9, 1513, Scottish and English armies clashed at the Battle of Flodden near Branxton in Northumberland, England. King James IV led his troops against the forces of Thomas Howard, Earl of Surrey, under orders from King Henry VIII. Despite early momentum, the Scots were hindered by difficult terrain and English longbowmen. James IV was struck down during the fighting, becoming the last British monarch to die in battle. The defeat decimated much of the Scottish nobility and cavalry, leaving the kingdom vulnerable. Flodden marked a significant setback in Scotland’s involvement in the War of the League of Cambrai. The battle had lasting political and social repercussions, including a period of regency under James’s widow, Margaret Tudor. Flodden remains one of the bloodiest battles in British history.
1513 James IV of Scotland Battle of Flodden War of the League of Cambrai
1543day.year

Mary Stuart, at nine months old, is crowned "Queen of Scots" in the central Scottish town of Stirling.

At nine months old, Mary Stuart is crowned Queen of Scots in Stirling in 1543, positioning her as a key figure in Scotland’s turbulent history.
On September 9, 1543, Mary, Queen of Scots, was crowned at the Church of the Holy Rude in Stirling, Scotland. The infant monarch succeeded her father, King James V, who died earlier that year. Nobles of Scotland swore fealty to the tiny queen and vowed to protect her realm during her minority. The coronation ceremony blended Catholic ritual with ancestral Scottish traditions. Mary’s early reign was dominated by regents, including her mother, Mary of Guise, navigating between pro-French and pro-English factions. Her crowning in Stirling Castle solidified her royal status and Gaelic heritage. The event set the stage for the complex alliances and conflicts that defined her life and the Reformation in Scotland. Mary’s legacy as queen consort of France and later contested monarch would shape British history for decades.
1543 Mary Stuart crowned Queen of Scots Stirling
1561day.year

The ultimately unsuccessful Colloquy of Poissy opens in an effort to reconcile French Catholics and Protestants.

The Colloquy of Poissy was a major 1561 assembly aiming to reconcile French Catholics and Protestants, ultimately failing to bridge their religious divide.
In September 1561, King Charles IX of France called together leading theologians from Catholic and Protestant factions to the royal court at Poissy. The aim was to narrow theological differences and prevent religious civil war in France. High-ranking clerics such as the Catholic Bishop of Rennes and Protestant theologian Theodore Beza participated in rigorous debates. Despite hopes for compromise, deep doctrinal disagreements over the Eucharist and papal authority persisted. The colloquy ended without a formal resolution, reinforcing divisions that would soon lead to the French Wars of Religion. Though unsuccessful, the Colloquy of Poissy is remembered as a key moment in early modern attempts at religious coexistence.
1561 Colloquy of Poissy French Catholics Protestants
1588day.year

Thomas Cavendish in his ship Desire enters Plymouth and completes the first deliberately planned voyage of circumnavigation.

In 1588, English explorer Thomas Cavendish completed the first intentionally planned circumnavigation of the globe, returning to Plymouth aboard the Desire.
In July 1586, English privateer Thomas Cavendish departed Plymouth in his ship Desire, intent on a planned circumnavigation of the globe. Over the next two years, he raided Spanish vessels along the Pacific coast before crossing the Pacific Ocean and the Indian Ocean. Cavendish rounded Cape Horn and the Cape of Good Hope, demonstrating skilled command of the seas. He faced storms, crew mutinies, and scurvy, yet continued his voyage with determination. On September 9, 1588, Desire returned to Plymouth, completing the first intentionally planned English circumnavigation. The expedition boosted England’s maritime prestige and inspired future explorers. Cavendish’s success cemented his reputation as a pioneering navigator.
1588 Thomas Cavendish Desire Plymouth voyage of circumnavigation