Mongol Invasion of Europe (1241): Legnica, Mohi and Retreat

The Mongol invasion of Europe in 1241 was the westernmost campaign of the Mongol Empire. Mongol armies under Batu and the general Subutai swept through Poland and Hungary, destroying a Polish-German army at Legnica and the main Hungarian army at Mohi within two days in April 1241. After devastating Hungary for a year, they suddenly withdrew in the spring of 1242, and the question of why they left has fascinated historians ever since.

Background: the great western campaign

In 1235 the Mongol leaders met in an assembly, or kurultai, at Karakorum and agreed to launch a major campaign to the west. Genghis Khan had assigned the western steppes to his eldest son Jochi, and Jochi’s son Batu was given command. With him went princes from every branch of the family, including Güyük, son of the Great Khan Ögedei, and Möngke, son of Tolui, along with the experienced general Subutai, who had led a famous raid into the region in 1221-1223.

The campaign began in 1236 with the conquest of Volga Bulgaria. The Mongols then turned on the Cumans (also called Kipchaks or Polovtsians) of the western steppe and the divided Rus principalities. Ryazan and Vladimir fell in the winter of 1237-1238, and Kyiv was stormed in December 1240, as described in the article on the Mongol invasion of Kievan Rus.

Fleeing the Mongols, the Cuman chief Köten led tens of thousands of his people into Hungary in 1239. King Béla IV accepted them in exchange for their conversion to Christianity and military service. The Mongols regarded the Cumans as runaway subjects, and a letter from Batu warned Béla to hand them over. Béla refused. The arrival of the nomads also caused friction with Hungarian nobles, who already resented the king’s efforts to recover royal lands.

The campaign in Poland

Early in 1241 the Mongols split their forces. A smaller army under Baidar and Kadan, grandsons of Genghis Khan, struck into Poland to stop the Poles and Bohemians from helping Hungary. Poland was then divided into several duchies ruled by princes of the Piast dynasty, with no single king to coordinate defence.

The Mongols took Sandomierz, defeated the knights of Lesser Poland at Chmielnik on 18 March 1241, and burned Kraków later that month. In early April they faced Duke Henry II the Pious of Silesia near Legnica. On 9 April they destroyed his army, killing Henry, at the Battle of Legnica. King Wenceslaus I of Bohemia, who was a day or two away with reinforcements, fell back to defend his own lands. The northern Mongol force then marched south through Moravia, plundering as it went, to rejoin the main army in Hungary.

The invasion of Hungary

Meanwhile the main army, led by Batu and Subutai, entered Hungary in March 1241 through the Carpathian passes, chiefly the Verecke Pass. Other columns crossed further south through Transylvania. On 12 March the Mongols overwhelmed the troops of the palatine Denis guarding the Verecke Pass, and within days they were raiding near Pest.

Béla gathered his army at Pest, but the kingdom was badly divided. When Mongol raiders appeared, rumours spread that the Cumans were in league with them. Köten was murdered in Pest by a mob in March 1241, and his furious followers left Hungary, plundering as they went south. Béla thus lost his most experienced light cavalry just before the decisive battle.

The Hungarian army followed the Mongols north-east to the Sajó River. On 11 April 1241, at the Battle of Mohi, the Mongols forced the bridge and crossed the river at another point, surrounded the Hungarian camp, and left a gap through which the fleeing troops were cut down over several days’ march. Many of the kingdom’s leading men died, including Ugrin, Archbishop of Kalocsa, and Matthias, Archbishop of Esztergom. Béla escaped to Austria, where Duke Frederick II of Babenberg took his treasure and three western counties as the price of shelter.

Why the Mongols won

The Mongol army’s victories rested on discipline, mobility and intelligence rather than numbers alone. Each soldier had several horses, allowing columns to cover long distances quickly and to converge at the right moment. Commanders gathered information through scouts and merchants and knew that Poland was divided and that Hungary’s nobles distrusted their king. Their mounted archers could wear down heavily armoured knights, and their engineers brought stone-throwing machines to the battlefield, as at the Sajó bridge.

A year of devastation

For the rest of 1241 the Mongols occupied the Hungarian plain east of the Danube. They set up a kind of administration, appointing officials and ordering the harvest to be gathered. Contemporary accounts describe mass killing of those who resisted or were no longer useful, the burning of villages, and famine that followed the destruction of crops.

The most vivid eyewitness description comes from Master Roger (Rogerius), an Italian churchman at Nagyvárad (modern Oradea), who was captured and later escaped. His work, known as the “Sorrowful Lament”, tells of refugees hiding in forests and marshes and of towns tricked into surrender. Thomas, Archdeacon of Split, wrote another important account.

In December 1241 or early 1242 the Danube froze, and the Mongols crossed into western Hungary. They stormed Esztergom, then the kingdom’s richest town, although its citadel held out, as did a few other stone fortresses such as Pannonhalma Abbey and Székesfehérvár. A force under Kadan pursued Béla, who had fled to the Dalmatian coast. In March 1242 the Mongols reached Split and Trogir, where the king took refuge on an island, but they could not reach him.

The withdrawal

In the spring of 1242 the Mongols abandoned Hungary. Kadan’s force went south through Bosnia, Serbia and Bulgaria, while Batu led the main army back to the steppes north of the Black Sea. By the end of 1242 they had gone.

Why they left is still debated. The traditional explanation is the death of the Great Khan Ögedei on 11 December 1241, which required the princes to return for the election of a successor. But Batu did not hurry to Mongolia; he stayed on the Volga and avoided the assembly for years. Other historians, such as Denis Sinor, have argued that the Hungarian plain could not support the vast herds of horses a Mongol army needed. In 2016 Ulf Büntgen and Nicola Di Cosmo used tree-ring evidence to suggest that a cold, wet spring in 1242 turned the plain into marshland, reducing pasture and mobility. Many historians think that several of these factors combined, and that the Mongols may have regarded the campaign as a raid that had already achieved its goal.

Key people

• Batu (c. 1205-1255): grandson of Genghis Khan, overall commander and later founder of the Golden Horde.
• Subutai (c. 1175-1248): veteran Mongol general and chief strategist of the campaign.
• Béla IV (1206-1270): King of Hungary, defeated at Mohi, who rebuilt the kingdom afterwards.
• Henry II the Pious (c. 1196-1241): Duke of Silesia, killed at Legnica.
• Köten: Cuman chief whose flight to Hungary helped provoke the invasion.

Consequences

Hungary suffered most. Estimates of its population loss vary widely, from about 15 percent to as much as half in the lowland regions, and the true figure cannot be known. After his return, Béla IV encouraged the building of stone castles across the kingdom, invited settlers, including Germans, and brought back the Cumans as allies. He is sometimes called Hungary’s “second founder”. A second, smaller Mongol invasion in 1285-1286 was repulsed, partly thanks to these new castles.

Batu, on his return, founded a state on the lower Volga later known as the Golden Horde, which dominated the Rus principalities for two centuries and raided Poland and Hungary again. In western Europe the invasion caused alarm. Emperor Frederick II and Pope Gregory IX were at war with each other and organised no effective response, but in 1245 Pope Innocent IV sent envoys to the Mongols to learn about them and try to prevent another attack.

Myths and facts

• Myth: Europe’s knights stopped the Mongol advance. Fact: the Mongols won every major battle in 1241; they left of their own accord.
• Myth: the Mongols withdrew only because of Ögedei’s death. Fact: this is one possible reason, but environmental and strategic factors are also widely discussed.
• Myth: the Kraków trumpet call, cut off mid-melody, recalls a trumpeter shot by a Mongol arrow in 1241. Fact: there is no medieval evidence for the story, which was popularised in the 20th century, notably by Eric P. Kelly’s novel The Trumpeter of Krakow (1928).

Timeline

• 1235: The kurultai decides on the western campaign.
• 1239: The Cumans under Köten take refuge in Hungary.
• 1240, December: The Mongols capture Kyiv.
• 1241, 12 March: The Mongols force the Verecke Pass into Hungary.
• 1241, 18 March: Polish knights are defeated at Chmielnik.
• 1241, 9 April: Battle of Legnica; Henry II is killed.
• 1241, 11 April: Battle of Mohi; the Hungarian army is destroyed.
• 1241, 11 December: The Great Khan Ögedei dies in Mongolia.
• 1242, March: Kadan’s force reaches the Dalmatian coast.
• 1242, spring: The Mongols withdraw from Hungary.

Why it matters

The invasion of 1241 showed that no European army of the time could match the Mongols in open battle, and it left Hungary devastated. Yet the sudden withdrawal meant that central Europe escaped the long Mongol rule that the Rus lands endured. The campaign changed how European kings built castles, opened the first diplomatic contacts between Europe and the Mongol Empire, and remains one of the great “what ifs” of medieval history.