In the Song Dynasty, in order to strengthen military centralization and prevent generals from seizing power. In March of the second year of Stegosaurus, Song Taizu cut off the important imperial post of Dujian. In July of the same year, Song Taizu released the military power of the military attache through a glass of wine, and the leadership of the imperial army was changed to the former government and the bodyguard officer, which were under the command of the former government, the stepping army and Ma Jun (three handsome) respectively. However, the three commanders have no right to send troops. In the Song Dynasty, the Privy Council was established in the central government to take charge of the military. The Privy Council is directly responsible to the emperor, and other officials are not allowed to ask. Although the Privy Council can send troops, it can't directly unify the army, which leads to the separation of the right to unify and adjust the army. At the same time, in the Song Dynasty, generals were often replaced to prevent personal forces from appearing in the army. The deployment of troops in the Song Dynasty can be described as "strong cadres and weak branches" and "internal weakness and external defense". There were four kinds of armies in Song Dynasty, namely, imperial army, Xiang army, Xiang army and Francisco army. The imperial army is the central army and the main force of Song Jun. Xiang army is a town soldier in each state and is controlled by the local governor. Rural soldiers are able-bodied men transferred by the authorities. Fan Bing is a frontier army of non-Han nationality.