Imprisonment by the Mongols At the age of 22, in 1449, he was imprisoned by the Mongols when, advised by Wang Zhen, he personally directed and lost t

Imprisonment by the Mongols

At the age of 22, in 1449, he was imprisoned by the Mongols when, advised by Wang Zhen, he personally directed and lost the Battle of Tumu Fortress against the Mongols under Esen Khan. His capture by the enemy force shook the Ming dynasty to its core and the ensuing crisis almost caused the dynasty to collapse were it not for the capable governing of a prominent minister named Yu Qian. Although Zhengtong was a prisoner of the Mongols, he became a good friend to the khan. Meanwhile, to calm the crisis at home, his brother Zhu Qiyu was installed as the Jingtai Emperor. This reduced Zhengtong's imperial status and he was granted the title of "grand emperor".