Around 900 BC, in Zhou Wangxiao, Qin Feizi, the ancestor of Qin Dynasty, was made a vassal by Zhou Wang for his meritorious service in raising horses. Later, the Qin people raised horses for the Zhou royal family and fought Xirong at the border. After Zhou Yiwang, the royal family of Zhou Dynasty declined gradually and had to rely on the Qin people to stabilize the peace in the western regions.

In 82 BC1year, Qin Zhuanggong was defeated by Xirong, and was named Doctor of Xishu by Zhou Xuanwang, and was given the land of Dog Hill (southwest of Lixian County, Tianshui City, Gansu Province) where the Rhoda family lived. In 77 1 BC, Zhou Youwang was attacked and killed by Xirong, and Qin Xianggong was appreciated by Zhou Pingwang for leading the troops to save Zhou Yougong. In 770 BC, Qin Xianggong sent troops to escort his drought-striken fields eastward, was made a vassal, and was given land to the west of Qishan. From then on, Qin officially became a vassal state of the Zhou Dynasty.

Qin was initially ignored by other vassal States because of its remote geographical location. It was not until Qin Mugong destroyed the 12 country established by Xirong, expanded its territory for more than 1,000 miles, and stabilized the home front that it laid the foundation as the four great powers in the Spring and Autumn Period. Most of the kings of Qin died in the crusade against Xirong, and the Qin people fought against Ren Rong all the year round, which enabled them to be good at fighting.

At the beginning of the Warring States, Wei attacked Qin for years and seized the land of Hexi. Qin was forced to retreat to the west of Luoshui. Now, Shang Yang was appointed to carry out political reform, so Qin became stronger and stronger, and gradually became the most powerful country in the middle and late Warring States period.

In 325 BC, Qin Huiwen became king. Before 3 16, Qin destroyed Shu, and since then Qin has officially become the country with the largest territory among the Seven Heroes of the Warring States Period.

Before 237, Ying Zheng, king of Qin, ascended the throne. During the decade from 230 to 22 1 year, the six countries were destroyed and the Qin Dynasty was established.