Battle of the Sajó River [Battle of Mohi]

Béla IV flees from Mohi, detail from Chronicon Pictum

Date April 11, 1241

Location Muhi on the Sajó River in northeastern Hungary

Opponents (* winner)
*Mongols
Hungarians
*Mongols Commander Subotai
Hungarians King Béla IV

Approx. # Troops
*Mongols As many as 120,000
Hungarians More than 100,000

Importance
The Mongols ravage eastern Hungary and Transylvania and gain access to all central Europe
The victory over a Hungarian army led by King Béla IV at Muhi on the Sajó River gave the Mongols access to all of Central Europe. Genghis Khan died in 1227, but his son and successor, Ogatai Khan, continued Mongol expansion. The Mongols conquered Korea in 1231 and defeated the Chin Empire during 1231–1234. In 1235 in the course of a conference with Mongol leaders, Ogatai outlined a plan of expansion in four areas: China, Korea, Southeast Asia, and Eastern Europe.

The offensive against Eastern Europe began in 1236–1237, when Ogatai sent 130,000 Mongols into the region. Batu Khan had nominal command, but Subotai exercised real command. Subotai defeated the Bulgars and then led his army across the frozen Volga River in December 1237. In the course of their winter campaign the Mongols destroyed the northern Russian principalities, culminating in the defeat and death of Grand Prince Yuri II of Vladimir in the Battle of the Sil River on March 4, 1237. At the same time, Mongol forces to the south entered the Ukraine, where they reorganized and reequipped their forces.

During the next two years Subotai consolidated Mongol control over eastern and southern Russia. While the states of Central and Western Europe knew little about Mongol conquests or intentions, the Mongols gathered accurate intelligence about the political situation to their west. Subotai began the offensive in November 1240 with 150,000 men, again campaigning in winter to achieve maximum mobility on horseback in the marshlands and across frozen rivers. When Kiev rejected surrender demands, Subotai captured it on December 6.

Leaving behind 30,000 men to control the conquered territory and maintain his lines of communication, Subotai invaded Central Europe with 120,000 men. The Mongols moved on four axes. Kaidu, grandson of Ogatai, commanded the northern flank; Batu and Subotai had charge of the two central forces; and Kadan, son of Ogatai, protected the southern flank. The two middle forces were to pass through the central Carpathians into Transylvania and then meet at Pest, on the east bank of the Danube.

Kaidu meanwhile moved into Silesia, defeating a Polish army under King Boleslav V at Kraków (Cracow) on March 3, 1241. To meet Kaidu, Prince Henry of Silesia put together a mixed force of some 40,000 Silesians, Germans, Poles, and Teutonic Knights. King Wenceslas of Bohemia marched north with 50,000 men to join them. However, Kaidu struck before the two opposing forces could join. In the hard-fought Battle of Legnica (known as the Battle of Liegnitz in German and also called the Battle of Wahlstatt) on April 9, 1241, Kaidu smashed Prince Henry’s army. Kaidu then halted, having achieved his aims of devastating North-Central Europe and preventing its armies from moving south.

The Mongol southern advance had gone well. In mid-April the Mongols secured Transylvania, and Kadan drove north through the Iron Gates to join Subotai. On March 12, 1241, Hungarian king Béla IV, informed of the Mongol advance, called a conference of nobles at Buda, on the west bank of the Danube, to discuss how to meet the threat. On March 15 the conferees learned that the Mongol advance guard had already arrived at Pest, just opposite Buda.

Sure that the Pest defenses could hold the attackers, Béla IV gathered some 100,000 men over the next two weeks. At the beginning of April he set out from Pest to meet the invaders, confident that he had sufficient strength to defeat them. The Mongols withdrew before Béla’s cautious advance. Late on April 10 about 100 miles northeast of Pest, the Hungarians encountered and defeated a weak Mongol force defending a bridge at Muhi on the Sajó River, a tributary of the Tisza. Béla IV then established a strong bridgehead on the east bank of the Sajó and camped for the night with the bulk of his force on the west bank in a strong defensive position of wagons chained together.

The Mongols attacked the Hungarians before dawn on April 11, 1241, striking the bridgehead with arrows and with stones hurled by catapults, followed closely by an infantry assault. The defenders fought fiercely, and the Hungarians sortied from the main camp to their aid.

They soon discovered that the attack was only a feint. Subotai had led 30,000 men across the river some distance south of the bridge, and this force now came in from the south and rear of the Hungarians. The Hungarians found themselves packed in a small space and devastated by Mongol arrows, stones, and burning naptha. King Béla IV managed to escape with some of his men to the north toward Pozsony (Bratislava). Although Mongol losses in the battle were heavy, the Hungarian force was virtually destroyed. It suffered between 40,000 and 70,000 dead, including much of the Magyar nobility.

With this Hungarian defeat, only the Danube River prevented a further Mongol advance. The Mongols held Eastern Europe from the Dnieper to the Oder and from the Baltic to the Danube. In a campaign lasting only four months, they had destroyed Christian forces numbering many times their own. Following the victory, the Mongols ravaged all eastern Hungary and Transylvania. With a majority of its settlements having been destroyed and a large portion of the population slain during the Mongol occupation, which lasted until 1242, the Hungarian state had to be completely reconstituted.

ReferencesAllsen, Thomas. Mongol Imperialism. Berkeley: University of California Press, 1987. Grousaset, Rene. The Empire of the Steppes: A History of Central Asia. New Brunswick, NJ: Rutgers University Press, 1970. Nicolle, David. The Mongol Warlords: Genghis Khan, Kublai Khan, Hulegu, Tamerlane. London: Brookhampton, 1998.