Map of the Chu–Han Contention and Early Han

This map covers the fall of Qin, the Chu–Han contention between Xiang Yu and Liu Bang, and the beginning of Han. From 209 BC (the first year of the Second Emperor of Qin), when Chen Sheng and Wu Guang raised troops, to 195 BC, when Liu Bang died and Lu Wan, King of Yan, fled to the Xiongnu, it records who held each city at the end of every 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.

The map shows Qin, Chen Sheng's Zhang Chu, the revived kings of the six old states (Chu, Zhao, Qi, Yan, Wei and Hán, written with a different character from Han), the Eighteen Kings enfeoffed by Xiang Yu in 206 BC together with his own Western Chu, Han, the kings of other surnames in early Han (Han Xin, Peng Yue, Ying Bu, Zhang Er and Zhang Ao, Wu Rui and others), and Nanyue and Minyue, which held cities. Small states such as the Three Qins (Yong, Sai and Di), Yin, Henan, Linjiang and Minyue are grey, with their names on the map. The Xiongnu, Donghu, Yuezhi, Gojoseon and others appear only as names at the edge of the map.

The darker bands mark the borders between powers. Where the colour fades out, no city's control can be said to have reached (nomad lands, mountains), and no border is drawn. The red square marks each power's capital that year. The bands under the year slider have two rows: Qin and Han above, and the line of Chu below (Zhang Chu, the Chu of Xiang Liang and King Huai, and Xiang Yu's Western Chu); click one to jump to its first year.

Under each state's name is the emperor reigning at the end of that year. The Second Emperor of Qin was killed in the eighth month of 207 BC, and Ziying, who was set up after him, called himself King of Qin, not emperor, so no name appears under Qin at the end of 207 BC. Liu Bang became King of Han in 206 BC but took the throne as emperor only in 202 BC, when Xiang Yu fell, so no name appears under Han before then.

In the calendar of this period the year began with the tenth month and ended with the ninth (or the intercalary ninth month in years that had one). For example, “the tenth month, winter, of the first year of Han”, when Ziying, King of Qin, surrendered to Liu Bang, fell at the start of winter in 207 BC by today's calendar, but counts here as the beginning of 206 BC. Years follow the Zizhi Tongjian.

For 100 major cities, we took from the histories who held each one at the end of each year (whose king or commanding general was there) and attached the source passage to every change of hands. The main source is the Zizhi Tongjian, checked against the Records of the Grand Historian (Shiji) and the Book of Han: 941 passages on city holders in all, each machine-checked to appear word for word in the text, and, for the Zizhi Tongjian, to fall under the heading of the right year. Afterwards, separate checkers went over every line again against the text, region by region (7 regions), and corrected errors and omissions in 14 cities. Sieges and temporary occupations given up within the year do not change a city's holder.

Where the histories record that a king was replaced but say nothing city by city, as with Xiang Yu's enfeoffment (206 BC) and the Han reunification (202 BC), the cities of the commanderies granted are counted together as that king's. The kingdoms of kings of the Han imperial family (Liu Fei, King of Qi; Liu Jiao, King of Chu; Liu Heng, King of Dai; and others) are coloured as Han, with the king's name under the state name.

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 mountain peoples) is left uncoloured, with the colour fading out.

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. Around cities that cannot be said to belong to anyone, however, the land is left blank even where a neighbouring power could reach it. 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.