section_path: History/Eastern Han (25–220 AD)
section_name: Eastern Han (25–220 AD)
paragraph_text: Eastern Han (25–220 AD)
  
  The Eastern Han (traditional Chinese: 東漢; simplified Chinese: 东汉; pinyin: Dōnghàn), also known as the Later Han (後漢; 后汉; Hòuhàn), formally began on 5 August AD 25, when Liu Xiu became Emperor Guangwu of Han. During the widespread rebellion against Wang Mang, the state of Goguryeo was free to raid Han's Korean commanderies; Han did not reaffirm its control over the region until AD 30.
  
  The Trưng Sisters of Vietnam rebelled against Han in AD 40. Their rebellion was crushed by Han general Ma Yuan (d. AD 49) in a campaign from AD 42 to 43. Wang Mang renewed hostilities against the Xiongnu, who were estranged from Han until their leader Bi (比), a rival claimant to the throne against his cousin Punu (蒲奴), submitted to Han as a tributary vassal in AD 50. This created two rival Xiongnu states: the Southern Xiongnu led by Bi, an ally of Han, and the Northern Xiongnu led by Punu, an enemy of Han.
  
  During the turbulent reign of Wang Mang, China lost control over the Tarim Basin, which was conquered by the Northern Xiongnu in AD 63 and used as a base to invade the Hexi Corridor in Gansu. Dou Gu (d. 88 AD) defeated the Northern Xiongnu at the Battle of Yiwulu in AD 73, evicting them from Turpan and chasing them as far as Lake Barkol before establishing a garrison at Hami. After the new Protector General of the Western Regions Chen Mu (d. AD 75) was killed by allies of the Xiongnu in Karasahr and Kucha, the garrison at Hami was withdrawn.
  
  At the Battle of Ikh Bayan in AD 89, Dou Xian (d. AD 92) defeated the Northern Xiongnu chanyu who then retreated into the Altai Mountains. After the Northern Xiongnu fled into the Ili River valley in AD 91, the nomadic Xianbei occupied the area from the borders of the Buyeo Kingdom in Manchuria to the Ili River of the Wusun people. The Xianbei reached their apogee under Tanshihuai (d. AD 181), who consistently defeated Chinese armies. However, Tanshihuai's confederation disintegrated after his death.
  
  Ban Chao (d. AD 102) enlisted the aid of the Kushan Empire, which controlled territory across South and Central Asia, to subdue Kashgar and its ally Sogdiana. When a request by Kushan ruler Vima Kadphises (r. c. 90 – c. 100 AD –) for a marriage alliance with the Han was rejected in AD 90, he sent his forces to Wakhan (modern-day Afghanistan) to attack Ban Chao. The conflict ended with the Kushans withdrawing because of lack of supplies. In AD 91, the office of Protector General of the Western Regions was reinstated when it was bestowed on Ban Chao.
  
  Foreign travellers to the Eastern Han empire included Buddhist monks who translated works into Chinese, such as An Shigao from Parthia, and Lokaksema from Kushan-era Gandhara. In addition to tributary relations with the Kushans, the Han empire received gifts from sovereigns in the Parthian Empire, as well as from kings in modern Burma and Japan. He also initiated an unsuccessful mission to Rome in AD 97 with Gan Ying as emissary.
  
  A Roman embassy of Emperor Marcus Aurelius (r. 161–180 AD) is recorded in the Weilüe and Book of Later Han to have reached the court of Emperor Huan of Han (r. 146–168 AD) in AD 166, yet Rafe de Crespigny asserts that this was most likely a group of Roman merchants. In addition to Roman glasswares and coins found in China, Roman medallions from the reign of Antoninus Pius and his adopted son Marcus Aurelius have been found at Óc Eo in Vietnam. This was near the commandery of Rinan where Chinese sources claim the Romans first landed, as well as embassies from Tianzhu in northern India in 159 and 161. Óc Eo is also thought to be the port city " Cattigara " described by Ptolemy in his Geography (c. 150 AD) as lying east of the Golden Chersonese (Malay Peninsula) along the Magnus Sinus (i.e. the Gulf of Thailand and South China Sea), where a Greek sailor had visited.
  
  Emperor Zhang 's (r. 75–88 AD) reign came to be viewed by later Eastern Han scholars as the high point of the dynastic house. Subsequent reigns were increasingly marked by eunuch intervention in court politics and their involvement in the violent power struggles of the imperial consort clans. In 92 AD, with the aid of the eunuch Zheng Zhong (d. 107 AD), Emperor He (r. 88–105 AD) had Empress Dowager Dou (d. 97 AD) put under house arrest and her clan stripped of power. This was in revenge for Dou's purging of the clan of his natural mother— Consort Liang —and then concealing her identity from him. After Emperor He's death, his wife Empress Deng Sui (d. 121 AD) managed state affairs as the regent empress dowager during a turbulent financial crisis and widespread Qiang rebellion that lasted from 107 to 118 AD.
  
  When Empress Dowager Deng died, Emperor An (r. 106–125 AD) was convinced by the accusations of the eunuchs Li Run (李閏) and Jiang Jing (江京) that Deng and her family had planned to depose him. An dismissed Deng's clan members from office, exiled them, and forced many to commit suicide. After An's death, his wife, Empress Dowager Yan (d. 126 AD) placed the child Marquess of Beixiang on the throne in an attempt to retain power within her family. However, palace eunuch Sun Cheng (d. 132 AD) masterminded a successful overthrow of her regime to enthrone Emperor Shun of Han (r. 125–144 AD). Yan was placed under house arrest, her relatives were either killed or exiled, and her eunuch allies were slaughtered. The regent Liang Ji (d. 159 AD), brother of Empress Liang Na (d. 150 AD), had the brother-in-law of Consort Deng Mengnü (d. 165 AD) killed after Deng Mengnü resisted Liang Ji's attempts to control her. Afterward, Emperor Huan employed eunuchs to depose Liang Ji, who was then forced to commit suicide.
  
  Students from the imperial university organized a widespread student protest against the eunuchs of Emperor Huan's court. Huan further alienated the bureaucracy when he initiated grandiose construction projects and hosted thousands of concubines in his harem at a time of economic crisis. Palace eunuchs imprisoned the official Li Ying (李膺) and his associates from the Imperial University on a dubious charge of treason. In 167 AD, the Grand Commandant Dou Wu (d. 168 AD) convinced his son-in-law, Emperor Huan, to release them. However, the emperor permanently barred Li Ying and his associates from serving in office, marking the beginning of the Partisan Prohibitions.
  
  Following Huan's death, Dou Wu and the Grand Tutor Chen Fan (d. 168 AD) attempted a coup against the eunuchs Hou Lan (d. 172 AD), Cao Jie (d. 181 AD), and Wang Fu (王甫). When the plot was uncovered, the eunuchs arrested Empress Dowager Dou (d. 172 AD) and Chen Fan. General Zhang Huan (張奐) favoured the eunuchs. He and his troops confronted Dou Wu and his retainers at the palace gate where each side shouted accusations of treason against the other. When the retainers gradually deserted Dou Wu, he was forced to commit suicide.
  
  Under Emperor Ling (r. 168–189 AD) the eunuchs had the partisan prohibitions renewed and expanded, while also auctioning off top government offices. Many affairs of state were entrusted to the eunuchs Zhao Zhong (d. 189 AD) and Zhang Rang (d. 189 AD) while Emperor Ling spent much of his time roleplaying with concubines and participating in military parades.