Tumu Crisis

Date	September 1, 1449
Location	Huailai County
Result	Oirat victory

Belligerents

Mongols

Ming Dynasty

Commanders and leaders

Tayisung Khan
Esen Taishi
Alag-Temur

Zhengtong Emperor (POW)
Wang Zhen †
Zhang Fu †

Strength

~20,000

~500,000

Casualties and losses

Unknown

200,000+

Coordinates: 40°23′N 115°36′E / 40.383°N 115.600°E / 40.383; 115.600

The Tumu Crisis (simplified Chinese: 土木之变; traditional Chinese: 土木之變; Mongolian: Тумугийн тулалдаан); also called the Crisis of Tumu Fortress (simplified Chinese: 土木堡之变; traditional Chinese: 土木堡之變) or Battle of Tumu (Chinese: 土木之役), was a frontier conflict between the Mongols and the Chinese Ming dynasty which led to the capture of the Zhengtong Emperor on September 1, 1449, and the defeat of an army of 500,000 men by a much smaller force.

In July 1449 Esen Tayisi (Chinese: 也先台吉) of the Mongols launched a large-scale, three-pronged invasion of China with his puppet khagan Toqtaq-Buqa. He personally advanced on Datong (in northern Shanxi province) in August. The eunuch official Wang Zhen, who dominated the Ming court, encouraged the 22-year-old Zhengtong Emperor to lead his own armies into battle against Esen. The size of Esen's army is unknown but a best guess puts it at some 20,000 men. The Ming army of about 500,000 was hastily assembled; its command was made up of 20 experienced generals and a large entourage of high-ranking civil officials, with Wang Zhen acting as field marshal.

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