Much of what came to constitute China Proper was unified for the first time in 221 B.C. In that year the western frontier state of Qin, the most aggressive of the Warring States, subjugated the last of its rival states, putting an end to the Warring States Period.
The King of Qin, Ying Zheng, proclaimed himself Qin Shi Huangdi (the First Emperor), a formulation of titles previously reserved for deities and the mythological sage-emperors. He wanted his successors to rule China forever with the title "Emperor of China II", "Emperor of China III", etc.
In consolidating power, the Qin Shi Huangdi imposed the State of Qin's centralized, nonhereditary bureaucratic system on his new empire in place of the Zhou's feudalistic one. The Qin Empire relied on the philosophy of legalism (with skilful advisors like Han Fei and Li Si). Centralization, achieved by ruthless methods, was focused on standardizing legal codes and bureaucratic procedures, the forms of writing and coinage, and the pattern of thought and scholarship. Characterss from the former state of Qin became the standard for the entire empire. To silence criticism of imperial rule, the emperor banished or put to death many dissenting Confucian scholars and confiscated and burned their books.
Qin aggrandizement was aided by frequent military expeditions pushing forward the frontiers in the north and south. To fend off barbarian intrusion (mainly against the Xiongnu in the north), the fortification walls built by the various warring states were connected to make a 5,000- kilometer-long Great Wall of China. A number of public works, including canals and bridges, projects were also undertaken to consolidate and strengthen imperial rule. A lavish tomb for the emperor, complete with a Terracotta Army was built near the capital Xianyang, a city half an hour from modern Xi'an. These activities required enormous levies of manpower and resources, not to mention repressive measures.
Endless labor in the later years of Ying Zheng's reign started to provoke widespread discontent. However, the emperor was still barely able to maintain stability by his tight grip on every aspect of lives of the Chinese.
During a trip with his beloved second son Ying Huhai in 210 BC, Ying Zheng died suddenly at Shaqiu prefecture. Ying Huhai, under the advice of two high officials - the Imperial Secretariat Li Si and the chief eunuchZhao Gao - forged the altered Emperor's will. The faked decree ordered Ying Zheng's first son, the heir Ying Fu Su, to commit suicide, and renamed Ying Huhai as the next emperor, and stripped the command of troops from Marshal Meng Tian - a faithful supporter of Ying Fu Su - and killed Meng's family also. Zhao Gao step by step seized the power of Ying Huhai, effectively made him a puppet emperor.
Within the first 3 months after Ying Zheng's death, widespread revolts by peasants, prisoners, soldiers and descendants of the nobles of the Six Warring States sprang up all over China. Chen Sheng and Wu Guang, two in a group of about 900 soldiers assigned to defend against the Xiongnu, were the leaders of the first rebellion.
In 207 BC, Zhao Gao forced Ying Huhai to commit suicide and replaced him by the murdered heir's son, Ying Ziying. Note that the title of Ying Ziying was "king of Qin" to reflect the fact that Qin no longer controlled the whole of China. The Chu-Han contention ensued. Ying Ziying soon killed Zhao Gao and surrendered to Liu Bang in 206 BC. The Qin Dynasty collapsed, three years after the death of Ying Zheng, and less than twenty years after it was founded.
Although the Qin Dynasty was short-lived, its legalist rule had a deep impact on later dynasties in China. The imperial system initiated during the Qin dynasty set a pattern that was developed over the next two millennia.
During the Qin Dynasty, since Shi Huangdi ("First Emperor"), there has been no posthumous name. The title of Shi Huangdi and Er Shi ("Second Generation") were used within the rulers' own lifetimes.
