Expansion of the Mongol Empire Under Ögedei

Ögedei, Genghis Khan’s third son, took over from his father and ruled the Mongol Empire from 1227 CE-1241 CE. One of his most important contributions to the empire was his conquest of Eastern Europe. These conquests involved invasions of Russia, Hungary, Volga Bulgaria, Poland, Dalmatia, and Wallachia. Over the course of four years (1237–1241), the Mongols quickly overtook most of the major eastern European cities, only sparing Novgorod and Pskov. As a result of the successful invasions, many of the conquered territories would become part of the Mongol Empire. This conquered region is sometimes  referred to as the Golden Horde.

The operations were masterminded by General Subutai and commanded by Batu Khan and Kadan, both grandsons of Genghis Khan. The Mongols had acquired Chinese gunpowder, which they deployed in battle during the invasion of Europe to great success, in the form of bombs hurled via catapults. The Mongols have been credited for introducing gunpowder and associated weapons into Europe. They were also masters at cavalry invasions and siege warfare, which threatened many of the principalities the Mongols hoped to capture.

Invasion and Conquest of Russian Lands

Ögedei Khan ordered his nephew (and grandson of Genghis Khan) Batu Khan to conquer Russia in 1235. (The territory was then called Rus’ and encompassed modern-day Russia, Ukraine, Poland, Belarus, and the Baltic states. Territories and cities were ruled over by princely dynasties, which often meant these regions were fragmented politically.) The main force arrived at Ryazan in December 1237. Ryazan refused to surrender, and the Mongols sacked it and then stormed through other Russian cities, including Vladimir Suzdal in the north, and Pereyaslav and Chernihiv in the south. Other major Russian cities—such as Torzhok, and Kozelsk—were captured between 1238 and 1240. Some cities, such as Novgorod in the north, were not attacked due to the dense march and forest land surrounding it. However, the princes ruling Novgorod acted as tax collectors for the Mongol Empire in the coming decades.

Afterward, the Mongols turned their attention to the steppe, crushing various tribes and sacking Crimea to the west. They returned to Russia in 1239 and sacked several more cities and finally took the southern Rus’ capital of Kiev, leaving behind their trademark destruction of both the population and city structures. This final attack sealed the Rus’ principalities’ fate, forcing princes to flee their regions or capitulate to Mongol taxation and rule.

Invasion into Central Europe

The Mongols continued to invade Central Europe with three armies. One army defeated the fragmented Poland at the Battle of Legnica in 1241. Two days later the armies regrouped and crushed the Hungarian army at the Battle of Mohi, killing up to a quarter of the population and destroying as much as half of the habitable dwellings. This decisive victory was partially due to the fact that Hungary was unprepared for an invasion and did not having a standing army ready to fight. It took a number of months for the Mongol army to subdue various power centers in Hungary. A major battle called the Mongol’s Siege of Esztergom in the capital of Hungary forced people to flee and a new capital was moved to Budapest. However, the Mongols had  a difficult time capturing fortified cities throughout Hungarian territories, which kept a total takeover from occurring. The Hungarian king Bela IV fled to Croatia during the initial attacks on his cities, and fortified structures throughout this territory helped keep the king and the local populations safe. However, Zagreb was sacked and destroyed in pursuit of the fugitive king and further territorial gains.

While the Mongol armies were fighting in Hungary and Croatia, they also pushed their forces into Austria, Dalmatia, and Moravia. Where they found local resistance, they ruthlessly killed the population. Where the locale offered no resistance, they forced the men into servitude in the Mongol army. They also ransacked Moldavia and Wallachia, plundering food stores and leaving the population in a precarious state.

End of the Mongol Advance

Although the Mongol forces were well-versed in cavalry and siege attacks, these two strategies also served as their weak points as they went farther westward. Many people in Hungary, Croatia, and Dalmatia had food stores at the ready for the long siege battles of the Mongol armies. Fortified cities and boggy or mountainous terrain also slowed down the light cavalry of the Mongol forces and gave European cities an advantage. Although politically fractured, European powers were uniting; even Hungarians who had survived the initial attack, or never engaged in battle, had begun a guerilla attack lead by survivors of the Hungarian royal family.

Along with all of these tactical challenges the charismatic Mongol leader, Ögedei, died in December 1241. His death forced the Mongol armies to halt their westward expansion, especially in the face of mounting difficulties, and hasten back the thousands of miles to Karakorum, their capital in Mongolia, to elect his successor. Although the expansion did not extend into Western Europe, the Mongol forces retained power over many major Eastern European cities for many decades. However, after Ögedei’s death, power disputes plagued the Mongol Empire and eventually weakened their extensive hold on such vast territories.

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