Dimensionality Reduction in the Song Dynasty

Modern historian Meng Yichuan traveled back in time to the late Southern Song Dynasty. He relied on modern industrial technology to reduce dimensions and attack the powerful families. He counterattacked from a poor scholar to the pinnacle of power. However, after overthrowing the villain, he was imprisoned by the emperor as a technological slave. In the end, he watched the civilization he protected being trampled to pieces by the Yuan Dynasty's cavalry.