Wang Mang's Xin Dynasty (8-22AD)
At the end of Western Han Dynasty, the emperors′maternal relatives gained more power because most emperors were young or weak. Many maternal relatives were appointed as officials of high ranks and had the rights to select fellow officials.
Wang Zhengjun was the empress of Emperor Yuan and mother of Emperor Cheng. After Emperor Yuan died, her relatives were placed in ruling positions in her son’s court. Her nephew, Wang Mang rise as the most powerful official in the court. He gained much public support on his rise and was famous for his outstanding competence.
Eventually, Wang Mang declared himself emperor of a new dynasty, the Xin (New). He began a ceremony in which a seal of precious stone was passed to the emperor. From then on, whoever held this seal was the official emperor. He conducted a series of reforms, which was called “Wang Mang’s New Policy”.

Eastern Han (or Later Han) (25-220AD)
Wang Mang was overthrown by a secret society of peasants known as the Red Eyebrows, because they painted their eyebrows red. The descendents of the Han dynasty eventually joined in the uprising.

became the first emperor of Eastern Han. As an emperor he was called Emperor of Guang Wu (Kuang-wu Ti).

In the late period of Eastern Han Dynasty, the court was increasingly moldering with internal struggles for powers and peasants uprising here and there throughout the country. In 184 A.D. another peasant uprising occurred. This movement was begun by the Yellow Turbans. This uprising served to unite the court factions who had previously been fighting one another, because they needed to unite to defeat the Yellow Turbans. Despite conquering them, Eastern Han did not return to a united state. Rather, three kingdoms emerged and the Han dynasty came to an end.

Science and Technology
Science and technology made remarkable strides. Paper, compass and seismograph were invented, which made China the first country in the world that invent and master the technologies. Steel was manufactured in large scale.

Foreign Communication

The period of the Han Dynasty (202 BC–220 AD) was a groundbreaking era in the history of Imperial China's foreign relations. The empire expanded westward as far as the rim of the Tarim Basin (in modern Xinjiang-Uyghur Autonomous Region), making possible relatively secure caravan traffic across Central Asia to Antioch, Baghdad, and Alexandria. The most important success is the exploration of “Silk Road”, which consisted of “the Continental Silk Road” and “the Maritime Silk Road”.During the reign of Emperor Wu of Han (141 BC–87 BC),the travels of

Chinese ambassador Zhang Qian opened up China's relations with many different Asian countries for the first time. He brought back detailed reports of lands that had been previously unknown to the Chinese, including details of his travels to the Greek-Hellenized kingdoms of Fergana (Dayuan) and the Greco-Bactrian Kingdom (Daxia), reports of Anxi (Persian Empire of Parthia), Tiaozhi (Mesopotamia), Shendu (India), and the Wusun Central Asian nomads.
After his travels, the famous land trading route called “the Continental Silk Road” leading from China to the Roman Empire was established. It became a main artery linking China and west Asian countries.
China was not limited to travel across land and mountains. During the 2nd century BC, the Chinese sailed past Southeast Asia and into the Indian Ocean, reaching India and Sri Lanka by sea.

Philosophy
Han established Confucianism as the official ideology under the rule of Emperor of Wu advised by Dong Zhongshu, a Confucian scholar. The Confucianism included not the pure studies of Confucius, but a

conglomeration of various other philosophies and superstitions. This changed the way that empire was run.

The emperors chose their officials based on merits and competence. Written examinations were used to identify the best qualified people for the positions. In the 2nd Century BC, an imperial university was established to teach students the five classics of the Confucian school to prepare them to become officials.
The Han Dynasty was the first peak in China’s imperial period, thus today a majority of Chinese people are refered to “People of Han”.