Internal Factors:

Corruption: The Dowager Queen made a right mess of things when she took the real ruling power from her grandson, the true Emperor who wanted to industrialize. The Dowager Queen took military funding to build herself a grand Summer Palace, which practically stopped Chinese military development. Her regressive beliefs influenced well-known government officials, who ignored the cries of starved commoners and sat behind their wall of riches, delightfully unaware to the threat of Europeans.

Rise of Nationalism: Intellectuals saw the only way to defeat the Europeans was to use European technologies against them, and hence the overthrow of the corrupt and out-dated Imperialist Qing Dynasty.

External Factors:

Foreign invasion: The invasion by Europeans was made easy by Qing Dynasty's backward military - the majority of the outnumbering Chinese Navy was sunk in less than a week (what use were wooden junks to steel monsters?). The British then subsequently supplied opium to China, and when the Qing government refused to trade opium, the Brits used it as an excuse to openly invade China, split Chinese territories in unequal treaties, committed atrocious things to the Chinese population and utterly undermined Qing rule.

Backward Imperialism: The last rulers of Qing Dynasty saw themselves as divine rulers of a perfect nation, and saw European inventions (such as the musket and cannons) to be useless dirt. Therefore they didn't industrialize as the Japanese did (Meiji Restoration), and therefore they seriously lacked behind.

Shi Huangdi (259-210 BC) was the first emperor of unified China in 221 BC. He reorganized the political and legal systems in China, and standardized and simplified the written Chinese language.

The Changes to the Empire

In order to consolidate the nascent empire, Qin Shi Huang reformed politics, economy and culture. In politics, he abolished the hereditary vassal system and established prefectures and counties, ruled directly by the emperor. Although law was based on the original rules of the Qin State, the emperor adopted some regulations of other rival states to form a workable code for the Qin Dynasty. He considered agriculture and commerce crucial and developed them concurrently. The tax system, monetary coinage and meteorology were all standardized. In culture, the emperor unified the Chinese characters in writing, which promoted the development of the Chinese culture. However, he also suppressed scholars who were not to his liking. Consequently, many opposing scholars were killed in Xianyang.

The Great Wall of China

The symbol of the Chinese ancient civilization, the Great Wall bears witness to Qin Shi Huang's centralism. He ordered conscript laborers to link together the defensive works against marauding nomads already built by the former states. That was the forerunner of the modern Great Wall. Another world-famous achievement is the Terracotta Warriors and Horses in Xian, which was discovered nearby the mausoleum of Emperor Qin Shi Huang. Both are the wonders of China. But during their construction, countless conscripts lost their lives.

Decline of the First Empire

Qin Shi Huang longed for longevity, so he sent his ministers to go on quests seeking an elixir of immortality. However, death claimed him before he could find success in that matter. The emperor departed from the world of the living in 210 BC while traveling. The Peasant Uprising led by Chen Sheng and Wu Guang broke out soon after Hu Hai, the second generation, assumed the throne. Accordingly, the Qin Dynasty came to an abrupt end in 206 BC.