Tumu Crisis

In the summer of 1449 the Oirat Mongol leader Esen invaded northern China, and the young Ming emperor Yingzong rode out in person to meet him. On 1 September, at the Tumu post station in today's Huailai County, west of Beijing, a far smaller Mongol force routed the exhausted imperial army and took the emperor prisoner. The episode, also called the Crisis of the Tumu Fortress, ranks among the worst military disasters in the history of the Ming dynasty.

The dynasty's founder, the Hongwu Emperor, and his son the Yongle Emperor had fought the Mongols aggressively, and the capital was moved north to Beijing in 1421. After Yongle's death in 1424, however, border defence decayed. Officers seized the farms meant to feed hereditary soldiers, training suffered, and the capital's garrison was often put to work on palaces and temples. The frontier rested on three fortified cities, Xuanfu, Datong and Beijing, with little depth between them.

North of the border, the Oirats had become the leading Mongol power in the 1430s. Their chief Toghon married his daughter to a puppet khan, Toghtoa Bukha, and when Toghon died in 1440, real power passed to his son Esen. Esen depended on trade in horses for Chinese tea, silk and luxuries to keep his followers loyal, but the Ming limited that trade to a few border markets. In 1449 the Ming supplied only a fifth of the goods his envoys asked for and refused a marriage between his son and an imperial princess. Esen turned to war.

In July 1449 the Mongols struck in three columns, towards Liaodong, Xuanfu and Datong. Encouraged by the powerful eunuch Wang Zhen, Yingzong announced that he would lead a punitive expedition himself. His ministers, among them the war minister Kuang Ye and his deputy Yu Qian, protested that the risk was unacceptable, but the emperor would not be moved. The army, often said to number about half a million though probably considerably fewer, was gathered in a few days and set out from Beijing on 4 August. It marched in heavy rain and short of food, and more men died of hunger than in skirmishes. Reaching Datong on 18 August, Wang Zhen judged an advance into the steppe too dangerous, declared victory and turned the army back.

As the column withdrew, Mongol attacks destroyed its rearguard, including 40,000 cavalry ambushed at Yao'er Gorge. On 31 August the army camped at Tumu rather than in the walled town of Huailai about 10 kilometres away, reportedly because Wang Zhen wanted to keep his baggage train with him. The camp had no water. The next morning the Mongols had surrounded it and offered talks; Wang Zhen instead ordered a move towards the river. About 20,000 Mongols, without Esen himself taking part, broke the thirsty army. Roughly half the Ming soldiers were lost, along with dukes, marquises, counts and hundreds of officials. Wang Zhen was killed, according to some reports by one of his own officers, and the emperor was captured.

In the capital, some officials urged a retreat south, but Yu Qian refused, and the court decided to stay. The emperor's brother Zhu Qiyu was made regent and in September took the throne as the Jingtai Emperor, robbing the captive of his value as a hostage. Datong and Xuanfu would not open their gates to Esen. When he reached Beijing on 27 October with some 70,000 men, Yu Qian, commanding about 220,000, held him off, and after five days the Mongols withdrew.

No territory changed hands, and trade relations recovered within months. Yingzong was released in September 1450 after more than a year in captivity, only to be confined by his brother in the Southern Palace. Esen's failure to profit from his victory weakened him; he proclaimed himself khan in 1453 and was assassinated in 1455. For the Ming, the shock prompted a reorganisation of government and army.

Our 1400 and 1500 maps show the Ming dynasty in China, with the Mongol lands of present-day Mongolia to the north.