Though Beijing was but a peripheral city to Chinese dynasties centered in Luoyang and Xi'an, it was to the nomads, an important entryway into China. The city's stature grew from the 10th century with successive invasions of China by Khitan, Jurchen and Mongols. In 938, the ascendant Khitan having unified the steppes founded the Liao Dynasty. It elevated Youzhou to be one of its four secondary capitals, renaming it Nanjing (南京) or the "Southern Capital". Thus, the City of Ji, ceded to the Liao as Youzhou, continued as Nanjing in what is today the southwest part of urban Beijing. Some of the oldest landmarks in southern Xicheng (formerly Xuanwu) and Fengtai Districts date to the Liao era. They include Sanmiao Road, one of the oldest streets in Beijing and the Niujie Mosque, founded in 996, and the Tianning Temple, built from 1100-1119.
The Lugou Bridge, first built in 1189, dates to the Jin DynastyThe Song Dynasty, after unifying the rest of China in 960, sought to recapture the lost northern territories. In 979, Song Emperor Taizong personally led a military expedition that reached and laid siege to Nanjing (Youzhou) but was defeated in the decisive Battle of Gaoliang River, just northwest of present-day Xizhimen. In 1122, the Song entered the Alliance on the Sea with the Jurchens, a nomadic people living northeast of the Liao in modern-day Manchuria. The two nations agreed to jointly invade the Liao and if successful, cede the Sixteen Prefectures to the Song. The Song faltered in their campaigns but the Jurchens were victorious and drove the Liao to Central Asia. The Jurchens captured Nanjing, looted the city and handed it to the Song, in exchange for tribute. Song rule of the city, renamed Yanshan (燕山), was short-lived.
The Jurchens founded Jin (金) Dynasty, and sensing Song weakness, invaded the Central Plains in 1125. They quick retook Beijing and renamed it Yanjing. In 1153, Jin Emperor Wanyan Liang moved his capital from Shangjing (near present-day Harbin) to the city, which was renamed Zhongdu (中都) or the "Central Capital." For the first time in its history, the city of Beijing became a political capital of a major dynasty.
The Jin expanded the city to the west, east, and south, doubling its size. On today's map of urban Beijing, Zhongdu would extend from Xuanwumen in the northeast to the Beijing West Railway Station to the west, and south to beyond the southern 2nd Ring Road. The walled city had 13 gates, four in the north and three openings in each of the other sides. Remnants of Zhongdu city walls are preserved in Fengtai District. The Jin emphasized the centrality of the regime by placing the walled palace complex near the center of Zhongdu. The palace was situated south of present-day Guang'anmen and north of the Grand View Garden. Paper money was first issued in Beijing during the Jin. The Lugou Bridge, over the Yongding River southwest of the city, was built in 1189.
Genghis Khan at Zhongdu
The first Mongol siege of Beijing in 1213-1214. The city fell in the second siege of 1214-1215.
Genghis Khan receiving Jin envoys and the Qiguo Princess.Illustrations from the Jami' al-tawarikh by Rashid-al-Din Hamadani Bibliothèque Nationale de France, Département des Manuscrits, Division Orientale.Zhongdu served as the Jin capital for more than 60 years, until the onslaught of the Mongols in 1214. The Mongols, a tribal nomadic people in southern Siberia, had assisted the Jurchen in the war against the Khitans, but were not given the promised compensation. In 1211, the Mongols led by Genghis Khan took revenge against the Jin by invading northern China. By 1213, he had controlled most of Jin territory north of the Yellow River with the exception of the capital Zhongdu. In March 1214, he set up headquarters in the northern suburbs and with brother Hasar and three eldest sons, Jochi, Chagatai and Ögedei, began to besiege the city.[28] Though the Jin court was weakened by a palace coup, the city was protected by three layers of moats and 900 towers. When disease broke out within the Mongol ranks, Genghis Khan sent Muslim envoy Ja'far into the city to negotiate, and the Jin court agreed to a peace treaty by ceding territory and accepting vassal status. Among Genghis Khan's demands was marriage to a Jurchen princess. The Qicheng Princess, daughter of Jin Emperor Weishaowang, was designated for the Mongol chieftain. She along with 100 guards, 500 boys and girl servants, 3,000 bolts of cloth, and 3,000 horses were sent to Mongol camp.[32] The Qicheng Princess became one of the four main wives of Genghis Khan, who lifted the siege and withdrew north of the Juyong Pass.
The Jin Emperor Xuanzong, after considerable debate, decided to move the capital from Zhongdu to Kaifeng further to the south. In June 1214, as the Jin imperial procession departed the city, a detachment of Khitan guards rebelled at the Lugou Bridge and defected to the Mongols. Genghis Khan believed the Jin was trying to rebuild military strength further south in breach of the terms of peace and decided to reinvade the Jin. By winter, Mongol troops were again besieging Zhongdu.
In 1215, after a bitter siege in which many of the city's inhabitants starved, Zhongdu's 100,000 defenders and 108,000 households surrendered. The city was still looted and burned by the invaders. Zhongdu was renamed Yanjing. Among the captives taken from the city was a Khitan named Yelu Chucai, who persuaded Genghis Khan that while China could be conquered from the saddle, it could not be ruled from the saddle. Rather than converting northern China into pastures, it would be more beneficial for Mongols to tax the agrarian population. Genghis Khan took heed of Yelu Chucai's advice and Mongol pillaging eased. The Mongols continued to the campaign against the Jurchens until the capture of Kaifeng in 1234 which ended the Jin dynasty.