Ten Medieval Battles that Changed the World

Ten battles from the Middle Ages that would make a significant and lasting impact. While there are other medieval battles that are more famous, these encounters changed the course of nations and regions. Ranging from the fifth century to the fifteenth, they are listed chronologically.

Battle of Châlons – June 20, 451

The arrival of the Huns into Eastern Europe at the end of the fourth century AD would prove a major challenge to the Roman Empire. Under the leadership of Attila (c. 406–453), the Huns took control of huge swaths of territory and forced many other peoples to be their vassals. It seemed that the power of the Huns was invincible until their campaign into Gaul (now France) in the spring of 451.


The Huns and their allies would be challenged by the Roman general Aetius supported by the Visigoths, Franks and other Germanic tribes, and two sides would face off against each other on the Catalaunian Plains near the city of Châlons. The chronicler Prosper of Aquitaine, a contemporary of the battle, describes it this way:

Although the slaughter of all those who died there was incalculable – for neither side gave way – it appears that the Huns were defeated in this battle because those among them that survived lost their taste for fighting and turned back home.


There is much about the battle we don’t know, including how many countless thousands died in the fighting. Some historians do not believe the battle was that significant, but others see it as the beginning of the end of the Hunnic Empire – a quick end to, as after Attila’s death in 453 the Huns soon collapsed amid infighting and the revolt of their former vassals. Meanwhile, the Battle of Châlons is also seen as the last great victory of the Western Roman Empire, setting up an era where the Germanic peoples became the focus of Western Europe.

Battle of Hulao – 28 May 621

Battle of Luoyang-Hulao in 621 AD during which Tang dynasty defeated two of its rivals, Wang Shichong and Dou Jiande, during its unification of China Proper. Wikimedia Commons

The Tang dynasty (618-907) is regarded as a golden age of Chinese civilization, but it would have not been possible if they had not replaced the Sui Dynasty. This would happen at the Battle of Hulao.

In the previous year the Tang prince Li Shimin led a campaign against the city of Luoyang, the traditional capital of China for much of the first millennium AD. Despite a long and bitter siege, the defenders of the city held out, hoping to get reinforcements from the warlord Dou Jiande. In the spring of 621, the latter marched an army of between 100,000 and 120,000 men to relieve Luoyang, while Li Shimin used 10,000 of his own troops to occupy Hulao Pass to hold them off.

Despite having a much larger force, Dou Jiande’s army was held to a standoff that lasted weeks. Li Shimin ultimately would entice Dou Jiande and his tired and disorganized men into a battle, where the Tang prince attacked and routed their opponents – 50,000 men would be captured, including Dou Jiande. The prisoners would be brought to Luoyang, where the city’s defenders promptly surrendered.


Battle of Badr – 13 March 624

The death of Abu Jahl, and the casting of the Meccan dead into dry wells, from a 14th-century text

While only a few hundred people fought on each side, this battle, fought in western Arabia, was instrumental in the establishment of Islam. Two years earlier the Quraysh tribe had forced the Prophet Muhammad and his Muslim followers out of Mecca to the city of Medina. This would lead to a series of raids and attacks by the Muslims and their allies to disrupt trade into Mecca.

This low-level warfare culminated at the Battle of Badr. Muhammad had gathered 313 men to intercept a caravan carrying weapons for the Quraysh, but their plan was discovered and the Qurayshi leader Abu Jahl raised a force of 950 men to attack them. The two sides would begin a battle first with champions taking part in a three-on-three melee, followed by arrow attacks, and then a charge from the Muslim forces. The Qurayshi side then broke and fled, with Abu Jahl being killed during the rout.

The victory for the Muslims would ultimately lead to Muhammad returning to Mecca, and the religion of Islam spreading throughout the Arabian Peninsula.


Battle of Fontenoy – 25 June 841

15th-century depiction of the Battle of Fontenay

Fontenoy they call its fountain, manor to the peasant known,
There the slaughter, there the ruin, of the blood of Frankish race;
Plains and forest shiver, shudder; horror wakes the silent marsh. ~ opening lines by Angelbert, a soldier who took part in the battle.

The Carolingian Empire dominated much of Western Europe during the first half of the ninth century. It could have endured had not its ruler, Louis the Pious, decided to split up the realm among his three sons. This division did not please Lothair I, Louis’ eldest son, and along with his nephew Pepin II, he went to war against his two brothers.

Not much is known about this medieval battle, but it ended with a victory for Charles the Bald and Louis the German. Two years later the Treaty of Verdun was signed, which ended the war and created the states that would become France and Germany.

Battle of Hastings – 14 October 1066

The death of King Edward the Confessor in January of 1066 would lead to a scramble for power in Anglo-Saxon England. The country would see two invasions – the first by King Harald Hardrada of Norway, which would be defeated by Harold Godwinsson. Harold would then have to defend his claim to the throne against William, Duke of Normandy.


The clash between the Anglo-Saxons and the Normans would take place near the village of Hastings, in a day’s long encounter that would leave Harold dead. By the end of 1066 William was crowned King, and the Anglo-Norman era had begun. It would bring about even greater ties between the British Isles and continental Europe, and would put England on a course to become a major power in the world.

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Battle of Manzikert – 26 August 1071

Map of the campaign of Malazkirt/Manzikert between Seljuks and Byzantines in 1071. Image by Bakayna / Wikimedia Commons

The crusades from Western Europe to the Holy Land would probably not have occurred if the Byzantine Empire had not experienced such a devastating defeat as that which took place in what is now eastern Turkey.

The battle was started by Emperor Romanos IV Diogenes, who had wanted to regain some lost territory from the Seljuq Turks. While he was sending envoys to the Seljuq leader Alp Arslan to renew a peace treaty, he also led a force of 40,000 men out of Constantinople. Romanos’ campaign was bungled with tactical mistakes and desertions, and soon the Byzantines would be attacked and defeated by the Seljuks. Emperor Romanos would be taken prisoner, and then released by Alp Arslan, only to come home to a rebellion that would see him deposed.

The defeat at Manzikert is widely seen as the beginning of the decline of the Byzantine Empire, with the Seljuqs and other Turkish peoples coming to dominate Anatolia. The Byzantines would also call on Western Europe for more military reinforcements – this would be one of the catalysts for the First Crusade (1095-1099).

Battle of Legnano – 29 May 1176

Frederick Barbarossa, like many other rulers of the Holy Roman Empire, found controlling his territories in Italy to be very difficult. Cities such as Venice, Milan and Genoa, supported by the Papacy in Rome, formed the Lombard League in 1167 to oppose the Empire and gain greater autonomy. Barbarossa was keen to defeat this alliance, and launched several campaigns into northern Italy.

The two forces would meet near the town of Legnano. The Imperial army gained the early advantage, routing the Lombard cavalry, but when they faced a determined infantry, Frederick’s forces could not break them in a tough and bloody battle. When the Lombards counter-attacked and Frederick was thrown off his horse, his army panicked and fled.

Imperial power in northern Italy was lost, leaving the major Italian cities to largely govern themselves and become the wealthiest states in medieval Europe.

Battle of Bouvines – 27 July 1214

King Philip II of France’s victory at Bouvines, 15th-century illustration by Vincent of Beauvais

In the year 1214 an alliance was formed consisting of the Holy Roman Empire, England, Flanders, Holland, Lorraine, Brabant, Linburg and other states – their aim was to break the power of the King of France, Philip Augustus.

The alliance had over 9000 men on the side when they faced off against a French army of about 7500. The heavy fighting gradually wore down the alliance, and Emperor Otto IV would almost find himself captured. The French forces won the day, taking several important prisoners. Moreover, it solidified the Kingdom of France as the leading power in Europe for several generations.

Battle of ʿAyn Jalut – September 1260

The thirteenth century would see the Mongols emerge out of eastern Asia to form the largest land empire the world has ever seen. They would go on to conquer territories from China to Hungary. Perhaps their most impressive campaign was led by Hulagu Khan – he led a massive army that marched into the Middle East, conquering Iran and the Abbasid Caliphate in Baghdad. The Mongols were supposed to go all the way to the Nile River, thus setting up a state that would control the Eastern Mediterranean.

They would meet their match against the Mamluks, the former slave soldiers that had only recently taken power in Egypt. Having also come from the Eurasian Steppe, the Mamluks used the same tactics as the Mongols, and at ʿAyn Jalut (in what is now northern Israel) they destroyed a Mongol force.

The Mamluk victory allowed them to take back Syria from the Mongols, and prevent Hulagu Khan from completing his conquest of the Middle East. The Mongols would form the Ilkhanate and continue the war against the Mamluks for another fifty years, but the fortunes of the heirs of Genghis Khan would drop in the wake of this defeat.

Battle of Grunwald – 15 July 1410

The battle as depicted in the Berner Chronik of Diebold Schilling

Also called the Battle of Tannenberg as well as the Battle of Žalgiris, this conflict pitted a military order known as the Teutonic Knights against the Kingdom of Poland and their ally the Grand Duchy of Lithuania. The Teutonic Knights had been a major presence in Eastern Europe since the early thirteenth century, carving out a territory for themselves as they tried to eradicate the pagan religions.

Their rivalries with the Poles and Lithuanians would last for decades, and eventually lead to a Polish-Lithuanian alliance that would fight this major battle against the Teutonic Knights. It is believed that as many as 60,000 men took part in this battle, making it one of the largest ever to be fought in medieval Europe.

The battle would end with the Teutonic Knights defeated and most of their leadership dead or taken prisoner. In the immediate aftermath of the battle the military order was able to hold onto most of its lands, but they would continue to decline in strength in the following decades. Meanwhile, the Polish-Lithuanian union would solidify, leaving them the largest power in Eastern Europe until the 18th century.

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