Shang Yang's change of law, the background of what the land has changed into what the slave owners become what the slaves and the poor become

The Shang Yang Reform was an important political and social reform during the Warring States period, the core content of which was the abolition of the feudal system, the establishment of private ownership of land by the landowning class, the implementation of measures such as rewarding cultivation and war, and the awarding of titles on the basis of merit.

In terms of the land system, the land system in Qin before Shang Yang's change of law was that of feudal lordship, where the peasants were dependent on the lords and lacked production autonomy and land ownership. After Shang Yang's change of law, private ownership of land was introduced, and peasants were allowed to buy and sell land and were taxed according to the amount of land they actually possessed. This measure motivated the peasants and promoted the development of agricultural production.

In terms of class relations, the social class in Qin before Shang Yang's change of law was divided into slave owners and slaves, and a large number of poor people. Slave owners owned a great deal of land and wealth, but were burdened with heavy obligations, such as maintaining water conservancies and building palaces. Slaves, on the other hand, were bound to the land and lacked freedom and rights. After the Shang Yang Reform, measures such as "abolishing the privileges of slave-owning aristocrats, rewarding cultivation and warfare, and awarding titles according to merit" were implemented, breaking the privileged status of slave-owning aristocrats and allowing commoners to rise to become officials and commanders of armies, thus facilitating the mobility of and changes in the social strata.

To summarize, the land system of Qin before Shang Yang's change of law was the feudal lord land ownership system, and the social class was divided into three grades: slave masters, slaves and the poor. After Shang Yang's change of law, the private ownership of land and measures such as rewarding cultivation and war and awarding titles according to merit were implemented, which broke the privileged status of the slave-owning aristocracy and facilitated the mobility and change of social classes.