Original: Battle of Tumu Fortress : The Oirat Mongols defeat the Ming Dynasty army and capture the Zhengtong Emperor of China ; the latter is officially deposed while his brother ascends as the Jingtai Emperor the next year .
Simplified: Ming Dynasty army and capture the Zhengtong Emperor of China ; the latter is officially deposed while his brother ascends as the Jingtai Emperor the next year in 1450 .