Map of Song, Liao, Jin and Western Xia

This map covers China from 960, when Zhao Kuangyin founded the Song, to 1279, when the Southern Song fell at the Battle of Yamen. For every year it records who held each city at the end of the year, taken from the histories, and draws each power's territory from that. Move the year to watch the borders shift; click a city to see who held it, year by year, with the source passages.

Besides Song (Northern and Southern), Liao, Jin, Western Xia and the Mongols (Yuan from 1271), the map shows every state and power that held cities. Dali in Yunnan, Gusiluo's Qingtang, the Qi of Liu Yu set up by Jin, the Eastern Xia of Puxian Wannu, who made himself independent in Liaodong in the last years of Jin, and others are drawn in colour. Powers that briefly held cities, such as the warlords of the years when Jin replaced the Northern Song (Li Cheng, Kong Yanzhou, Sang Zhong and others) and Li Quan in Shandong and northern Huai in the last years of Jin, are grey, with only their names. Western Liao, the Qocho Uyghurs and others lie beyond the map, so only their names are placed at its edge.

The darker bands mark the borders between powers. Where the colour fades out, no city's control can be said to have reached (nomadic lands, mountains), and no border is drawn. The red square marks each power's capital that year. The bands under the year slider show, from the top, Song, the northern dynasties (Liao, Jin, the Mongols, Yuan) and the Li family of Xiazhou (the Dingnan Army, then Western Xia); click one to jump to its first year.

Under each state's name is the emperor reigning at the end of that year. For the Mongols, names start with Kublai (Shizu, enthroned in 1260): the rulers from Genghis Khan to Möngke are not in the site's list of emperors, so their names do not appear. “The end of the year” is the last day of the Chinese calendar year: Emperor Huizong handed the throne to Emperor Qinzong in the twelfth month of the seventh year of Xuanhe, which fell in January 1126 by the Western calendar but counts here as the end of 1125.

The years 960–979 overlap with the Five Dynasties and Ten Kingdoms map. For these 20 years, so that both maps show the same cities, the same holders and the same colours, the research for the Five Dynasties map (which traced the prefectures of the Ten Kingdoms one by one) is used as it is. Cities found only on this map appear from 980. (There are 39 cities found only on the Five Dynasties map, so this map has 280 cities in all.)

For 241 major cities, we took from the histories who held each one at the end of each year (whose prefect or commanding general was there) and attached the source passage to every change of hands. The main source is the Xu Zizhi Tongjian, with the Xu Zizhi Tongjian Changbian for the first half of the Song, the Jianyan Yilai Xinian Yaolu for the years of the wars between Song and Jin, and checks against the Histories of Song, Liao, Jin and Yuan. From 980 there are 1,281 passages in all, each machine-checked to appear word for word in the corresponding line of the text, and, for the Xu Zizhi Tongjian, to fall under the heading of the right year. After this, separate reviewers went back over every line against the text for each of 15 regions and corrected errors and omissions in 74 places. Sieges and occupations that were given up within the year do not change a city's holder.

In years when one dynasty replaced another (1127, Northern Song to Southern Song; 1137, when Qi was abolished and Jin ruled directly; 1271, when the Mongols took the dynastic name Yuan), every city held by the old dynasty at the end of the previous year is passed as a whole to the new one (a change is entered for that year even where there is no passage for the individual city). The Li family of Xiazhou is shown as the Dingnan Army (grey) before 1038, when Li Yuanhao proclaimed himself emperor, and as Western Xia from 1038.

The borders are inferred by machine from who held the cities. The land is divided into 4 km squares, and each square is given to the power whose city can be reached from it with the least effort, allowing for steep mountains and the difficulty of crossing great rivers. Land far from every city (steppe, plateau, the lands of upland peoples) is left uncoloured, with the colour fading out. The surroundings of cities that cannot be said to belong to anyone (ruined and abandoned) are not coloured either.

Where the cities of one power lie apart and its colour breaks off, they are joined by a band along a route that does not cross another power's land (up to about 400 km on level ground). Gaps surrounded on all sides by the powers' land and the sea, and gaps in the mountains south of the Qinling that reach deep into a power's land, are filled with the colour of the nearest power. A city surrounded by another power's land (an exclave) is drawn as a circle about 36 km in radius.

Borders at the time were zones rather than lines, and the lines on this map show only roughly where those zones lay.