The Di or Beidi (Northern Di) were various ethnic groups who lived north of the Chinese (Huaxia) realms during the Zhou dynasty. Although initially described as nomadic, they seem to have practiced a mixed pastoral, agricultural, and hunting economy and were distinguished from the nomads of the Eurasian steppe (Hu) who lived to their north. Chinese historical accounts describe the Di inhabiting the upper Ordos Loop (mostly in northern Shaanxi) and gradually migrating eastward to northern Shanxi and Hebei, where they eventually created their own states like Zhongshan and Dai. Other groups of Di seem to have lived interspersed between the Chinese states before their eventual conquest or assimilation.
The ancient Chinese, whose Xia, Shang, and Zhou states flourished along the Fen, Yellow, and Wei valleys, discussed their neighbors according to the cardinal directions. The "Four Barbarians" (Siyi) were the Di to the north, the Man to the south, the Yi to the east, and the Rong to the west. These came to be used as generic chauvinistic pejoratives for different foreign peoples long after the Chinese conquests of the original tribes and so are all usually translated as "barbarian" in English.
Beidi tribes, ethnic groups, or states were sometimes distinguished as belonging to the "Red Di" (, Chidi), the "White Di" (, Baidi), or "Tall Di" (, Changdi). The Xianyu, Fei, Zhongshan, and Dai kingdoms were founded by White Di.
The people of those five regions--the Middle states, and the [Rong], [Yi], (and other wild tribes round them)--had all their several natures, which they could not be made to alter. The tribes on the east were called [Yi]. They had their hair unbound, and tattooed their bodies. Some of them ate their food without its being cooked. Those on the south were called Man. They tattooed their foreheads, and had their feet turned in towards each other. Some of them (also) ate their food without its being cooked. Those on the west were called [Rong]. They had their hair unbound, and wore skins. Some of them did not eat grain-food. Those on the north were called [Di]. They wore skins of animals and birds, and dwelt in caves. Some of them also did not eat grain-food. The people of the Middle states, and of those [Yi], Man, [Rong], and [Di], all had their dwellings, where they lived at ease; their flavours which they preferred; the clothes suitable for them; their proper implements for use; and their vessels which they prepared in abundance. In those five regions, the languages of the people were not mutually intelligible, and their likings and desires were different. To make what was in their minds apprehended, and to communicate their likings and desires, (there were officers)--in the east, called transmitters; in the south, representationists; in the west, [Di-dis]; and in the north, interpreters.
The Di were often associated with the Rong; both were considered more warlike and less civilized than the Yi or Man. According to the Records of the Grand Historian, the ancestors of the Zhou lived in lands near the Rong and Di for fourteen generations, until Gugong Danfu led then away to the mid-Wei River valley where they built their capital near Mount Qi.
During the Eastern Zhou, the Chinese states--particularly Jin--expanded into Di territories, after which the Di were often their enemies. The "White Di" lived north of Qin and west of the Yellow River in what is now northern Shaanxi through the first half of the Spring and Autumn Period; tribes began crossing the river into northern Shanxi in the second half.
The Di eventually also established treaties of marriage and trade with the various Chinese states. The Jin prince Chong'er fled to his mother's family among them for many years until assassins sent by his brother forced him to begin wandering through the Chinese states.
The Xianyu and "White Di" moved east from the areas around the Yellow River in north Shaanxi and northwest Shanxi into the Taihang Mountains of Shanxi and Hebei during the 6th centuryBC. The "White Di" were especially numerous on the upper reaches of the Xinding or Hutuo Valley.
In 569BC, the Dao Duke of Jin announced a new peaceful policy towards the barbarians (, he Rong). He ended Jin's expansionist invasions of foreign lands and instead bartered with their leaders, purchasing territory for valuable Chinese objects like ritual bronzes and bells. During this period, the "White Di" began to move east of Taiyuan and the Taihang Mountains.
From the Taiyuan Basin, Jin pushed east through the Jingxing Pass () and attacked the "White Di" in the Taihang Mountains (530-520BC). By this time, the Di had walled towns like Fei, Gu, and Qiu You () and fought on foot.