It was protected from adjacent states and barbarian tribes with natural barriers. Therefore this region became one of the earliest centers of iron metallurgy in ancient China. Trade with northern neighbors and states of Central Asia and agriculture were basic branches of economy.
Before 500BC state of Qin did not take an active part in an internecine struggle of Chinese kingdoms and was considered relatively weak. Strong, persistent leaders and gifted commanders were required to use current potential in full scope. Shang Yang (390BC - 338BC) and Han Fei (280BC – 233BC), who had been statesmen at the end of the Warring States period, strengthened position of Qin among its competitors. Both of them were “credited with fostering Qin’s growth and categorized somewhat loosely as ‘Legalists’. They both had visited other kingdoms; and both met a violent death thanks to animosities.” (Loewe 12 - 18)
As a leader and reformer Shang Yang could be compared with Qin Shi Huangdi, because they strived for building military-bureaucratic state. Both of them rejected principles of Confucianism such as hierarchy, patriarchal concept of power, family clans etc. According to Shang Yang, idleness and lack of discipline are the main reasons of state decline. Lack of governmental control over them causes economic and agricultural recession. Reforms of Yang and Huangdi weakened positions of patrimonial aristocracy as the ruling class, because preliminary they had exclusively comprised officialdom. “The situation changed when Shi Huang Di successfully unified China under Qin in 221 B.C. with Li Si as his chancellor, by using effective military forces formed by Shang Yang’s reforms. After unification, the emperor decided to abolish feudalism and adopt Junxianzhi, a centralized system in which all the regions are governed by aristocrats appointed by the emperor, rather than as an individual