Despite its military strength, the Qin Dynasty did not last long. When the first emperor died in 210 BC, his son was placed on the throne by two of the previous emperor's advisers, in an attempt to influence and control the administration of the entire dynasty through him. The advisors squabbled among themselves, however, which resulted in both their deaths and that of the second Qin emperor. Popular revolt broke out a few years later, and the weakened empire soon fell to a Chu lieutenant, who went on to found the Han Dynasty. Despite its rapid end, the Qin Dynasty influenced future Chinese empires, particularly the Han, and the European name for China is thought to be derived from it.
Feizi, a descendant of the ancient political advisor Gao Yao, was granted rule over Qin City. During the rule of King Xiao of Zhou, the eighth king of the Zhou Dynasty, this area became known as the state of Qin. In 897 BC, under the regency of Gonghe, the area became a dependency allotted for the purpose of raising and breeding horses. One of Feizi's descendants, Duke Zhuang, became favoured by King Ping of Zhou, the thirteenth king in that line. As a reward, Zhuang's son, Duke Xiang, was sent eastward as the leader of a war expedition, during which he formally established the Qin.
Qin state first sent a military expedition into central China in 672 BC, though it did not engage in any serious incursions due to the threat from neighbouring tribesmen. By the dawn of the fourth century BC, however, the neighbouring tribes had all been either subdued or conquered, and the stage was set for the rise of Qin expansionism.Lord Shang Yang, a Qin statesman, introduced a number of militarily advantageous reforms from 361 BC until his death in 338 BC, and also helped construct the Qin capital, Xianyang. This latter accomplishment commenced in the mid-fourth century BC; the resulting city greatly resembled the capitals of other Warring States.
Of Shang Yang's reforms, the most notable one was advocating the philosophy of Legalism, which encouraged practical and ruthless warfare. In contrast, during the Zhou Dynasty and the ensuing Warring States Period, the prevalent philosophy had dictated war as a gentleman's activity; military commanders were instructed to respect what they perceived to be Heaven's laws in battle. For example, during the Warring States Period, Duke Xiang of Song was at war with the state of Chu, and had an opportunity to attack the enemy force, commanded by Zhu, while they were crossing a river. Instead, however, he waited for them to finish crossing, and allowed them to marshal their forces.
He was decisively defeated in the ensuing battle, and when, later, his advisors admonished him for such excessive courtesy to the enemy, he retorted, "The sage does not crush the feeble, nor give the order for attack until the enemy have formed their ranks." The Qin disregarded this military tradition, taking advantage of their enemy's weaknesses. A nobleman in the state of Wei accused the Qin state of being "avaricious, perverse, eager for profit, and without sincerity. It knows nothing about etiquette, proper relationships, and virtuous conduct, and if there be an opportunity for material gain, it will disregard its relatives as if they were animals." It was this Legalist thought combined with strong leadership from long-lived rulers, openness to employ talented men from other states, and little internal opposition that gave the Qin such a strong political base.
Another advantage of the Qin was that they had a large, efficient army and capable generals. They utilised the newest developments in weaponry and transportation as well, which many of their enemies lacked. These latter developments allowed greater mobility over several different terrain types which were most common in many regions of China. Thus, in both ideology and practice, the Qin were militarily superior. Finally, the Qin empire had a geographical advantage due to its fertility and strategic situation, protected by mountains that made the state a natural stronghold. Its expanded agricultural output helped sustain Qin's large army with food and natural resources; the Wei River canal built in 246 BC was particularly significant in this respect. During the Warring States Period preceding the Qin Dynasty, the major states vying for dominance were Yan, Zhao, Qi, Chu, Han, Wei and Qin. The rulers of these states styled themselves as kings, rather than using the titles of lower nobility they had previously held. However, none elevated himself to believe that he had the "Mandate of Heaven," as the Zhou emperors had claimed, nor that he had the right to offer sacrifices—they left this to the Zhou rulers.
Before their conquest in the fourth and third centuries BC, the Qin suffered several setbacks. Shang Yang was executed in 338 BC due to a grudge by the leader King Wu over a student who had been executed because of Shang Yang's insistence that law applied even to nobility. There was also internal strife over the Qin succession in 307 BC, which decentralised Qin authority somewhat. Qin was defeated by an alliance of the other states in 295 BC, and shortly after suffered another defeat by the state of Zhao, because the majority of their army was then defending against the Qi.
The aggressive statesman Fan Sui, however, soon came to power as prime minister even as the problem of the succession was resolved, and he began an expansionist policy that had originated in Jin and Qi, which prompted the Qin to attempt to conquer the other states. The Qin were swift in their assault on the other states. They first attacked the Han, directly east, and took the city of Yangdi in 230 BC. They then struck northward; the state of Zhao surrendered in 228 BC, and the northernmost state of Yan followed, falling in 226 BC. Next, Qin armies launched assaults to the east, and later the south as well; they took the Wei city of Daliang (now called Kaifeng) in 225 BC and forced the Chu to surrender by 223 BC. Lastly, they deposed the Zhou Dynasty's remnants in Luoyang and conquered the Qi, taking the city of Linzi in 221 BC.
When the conquests were complete in 221 BC, King Zheng – who had first assumed the throne of the Qin state at age 13 – became the effective ruler of China. He solidified his position as sole ruler with the abdication of his prime minister, Lü Buwei. He then combined the titles of the earlier Three Sovereigns and Five Emperors into his new name: Shi Huangdi or "First Emperor". The newly declared emperor ordered all weapons not in the possession of the Qin to be confiscated and melted down. The resulting metal was sufficient to build twelve large ornamental statues at the Qin's newly declared capital, Xianyang.
In 214 BC Qin Shihuang secured his boundaries to the north with a fraction (100,000 men) of his large army, and sent the majority (500,000 men) of his army south to conquer the territory of the southern tribes. Prior to the events leading to Qin dominance over China, they had gained possession of much of Sichuan to the southwest. The Qin army was unfamiliar with the jungle terrain, and it was defeated by the southern tribes' guerrilla warfare tactics with over 100,000 men lost. However, in the defeat Qin was successful in building a canal to the south, which they used heavily for supplying and reinforcing their troops during their second attack to the south. Building on these gains, the Qin armies conquered the coastal lands surrounding Guangzhou, and took the provinces of Fuzhou and Guilin. They struck as far south as Hanoi. After these victories in the south, Qin Shihuang moved over 100,000 prisoners and exiles to colonize the newly conquered area. In terms of extending the boundaries of his empire, the First Emperor was extremely successful in the south.
However, while the empire at times was extended to the north, the Qin could rarely hold on to the land for long. The tribes of these locations, collectively called the Hu by the Qin, were free from Chinese rule during the majority of the Dynasty. Prohibited from trading with Qin Dynasty peasants, the Xiongnu tribe living in the Ordos region in northwest China often raided them instead, prompting the Qin to retaliate. After a military campaign led by General Meng Tian, the region was conquered in 215 BC and agriculture was established; the peasants, however, were discontented and later revolted.
The succeeding Han Dynasty also expanded into the Ordos due to overpopulation, but depleted their resources in the process. Owen Lattimore said of both Dynasties' attempts to conquer the Ordos, "conquest and expansion were illusory. There was no kind of success that did not create its own reaction." Indeed, this was true of the dynasty's borders in multiple directions; modern Xinjiang, Tibet, Manchuria, Inner Mongolia, and regions to the southeast were foreign to the Qin, and even areas over which they had military control were culturally distinct.
