
The people of the Eurasian steppes, occupying a geological band from the Ukraine through to the grasslands above China, shared a common cultural & economic base due to the comparatively harsh environment & lifestyle.
In ancient times pastoralists moved with their flocks across these grasslands and in time from them came truly nomadic peoples, associated with horsemanship and their skill with a bow. Because of common experiences as well as movement of people & ideas across large distances there is a perceivable homogeneity in the material culture of these nomads during the bronze age and early iron-age. If we put aside questions over ethnicity (Indo-European/Turkic/Proto-Mongolian nomads) the artefacts of 'Scythian type' occur across a huge expanse of Eurasia amongst diverse tribes and are used as a marker of truly a nomadic societies emergence.
This 'Scythian' art & material culture of the nomads influenced the ancient Chinese, an example is the 'steppes-style' knife as adopted by Chinese and then used as early Chinese coinage ('knife' money) .
To the ancient Greeks, and even in post-Roman times, nomadic peoples might be collectively called 'Scythians', or to the Persians 'Saka' or to the Chinese the 'Hu'.
It is true that this is a simplification of different ethnicities and tribes. There were individual burial practices even inside sub-regions of the steppe as well as evidence for 'semi-nomadic pastoralists' & limited evidence for 'agriculturalists' inside the northern zone of ancient China. Some diversity is evidenced by archaeology but once the a true steppes nomad displaying the 'Scythian type assemblage' appear in the record to the north of China during the Eastern Zhou these people become of potent military force, and one which the ancient Chinese found very troublesome.
The unified Han empire faced difficulties with the raiding Xiongnu nomads, and this cultural confrontation continued later with northern people like the Mongols, Jurchen, Khitan, Manchu etc. some of whom managed to set up dynasties in their own right and conquer territory from the 'civilised' sedentary Chinese.
In earlier times the various & divided tribal people to the north offered only a short term threat to Zhou states, as the northern peoples (broadly known as tribes of the Jung or Di 'barbarians') were gradually conquered, assimilated, occupied or driven off. They made alliances or acted as auxiliaries for Zhou states but were a source of manpower or territory to be conquered as rival Chinese states sought such resources.
As the Zhou Chinese expanded north the archaic terms of Jung & Di gave way, and the 'Hu' are mentioned in ancient texts. This implies new groups were encountered in northward expansion as others were 'sinified' or in the ancient Chinese parlance; "cooked" (civilised/pacified).
In the earliest usage of 'Hu' this appears to be specifically applying to northern peoples rather than being used as a later general term for 'barbarian', i.e; DongHu.
The ancient Hu nomads are mentioned in the Eastern Zhou records as distinct from the non-Chinese 'Yue' tribes of the south for example {"Hu & Yue" as distinct people}.
The same Hu nomads the Chinese/Zhou encountered in driving northwards very likely include the people who during the late Warring States and Han period are further identified as the 'Xiongnu', the so-called ' Eastern Huns'.
For much detailed & scholarly discussion on the ancient period, Shang to Han, and their relationships with Jung & Di/Hu/Xiongnu of the northern zone see 'Ancient China and its Enemies; The Rise of Nomadic Power in East Asian History' by Nicola Di Cosmo.
Amongst the material culture of the nomads the curved & ring pommeled steppes-style knife (or 'Ordos' style knife, named for the region) was adopted by Chinese, and the Scythian artistic motif of animals, often in combat was also adopted. These are called 'zoomorphic' plaques. A common motif is predator devouring prey, and examples of this styles influence was found in the bronzes from the King of Zhongshans tomb dating from the late Warring States period.
The plaque below is a typical version of a steppes style plaque.

The cultural influence went both ways. Chinese items were sought by nomads, Chinese bronze mirrors are found inside the steppe for this reason.
The Northern influence on Chinese can be seen in socketed bronze halberds in Shang-Zhou sites, and Chinese weapons are also in turn found in the northern zone as people on the frontier filtered influences from the other culture. Chinese weapons eventually replaced tribal types in tombs inside of Yan state in Laioning province which is a symptom of the military expansion of the feudal Zhou and the displacement or assimilation of non-Chinese.
The appearance of weapons styles of the Northern cultural zone remains quite distinct from more orthodox Chinese weapon types. Generally speaking while the 'Scythian' type of arrowhead or halberd was socketed the 'Chinese' type used a tang. The short blades of the nomads also have differences in proportion and individualistic decoration that contrast with the Zhou-Chinese weapons from fuedal armouries.
The knife shown below is visibly of this "Hu" type. Yang Hongs calls these 'Hun' knives & swords. The use of the term Hun is potentially misleading given the Western experience with Attila & the Huns several centuries later, but it is a term that conveys some meaning to Westerners.
Cheng Dong's book (Ancient Chinese Weapons; A Collection of Pictures) refers to the knives as belonging to the Eastern Zhou period 'northern grasslands {culture} '.
An Eastern Zhou dating of these items fits into the period of the true steppes nomad cultures emergence north of China, and they are comparable to similar peoples knives found further from China of broadly 'Scythian type'.

The Warring States period, late East Zhou, is the time when Chinese Zhou expanded further northwards (Qin, Zhao & Yan states) and encountered the 'Hu'. It is across this new expanded frontier, along which several "long walls" of fortification were built, that the succeeding Han dynasty & Xiongnu nomads struggled across later.
The military capabilities of the Xiongnu in particular, especially when unified in a confederacy of tribes, or a 'steppes empire', required the Han to deal diplomatically with the Xiongnu on quite even terms. This was a necessity as the Chinese military (evident to Han realists at the time) could not match the skills of these mobile and tough horsemen. The unification of the Xiongnu under a supreme chieftain, Modun, was a crisis for the emerging Han Empire.
In swallowing pride the Han accepted a bi-polar relationship where the Xiongnu Chan-yu (supreme chieftain) was recognised as an Imperial 'brother' and sent royal Han brides. The Xiongnu were presented with silk, gold, millet and other resources in large volume.
This shows the anxiety this nomad military menace caused the early Western Han Emperors. The Han policy was far-sighted however and over generations of enduring Xiongnu raids under individual chieftains and still offering bribes to their Chan-Yu the Han army was gradually reorganised based on mobile cavalry and the preparations made for open war.
The Xiongnu made preparations too, and their influence stretched far across the steppes into central Asia. Many of the central Asian states paid the Xiongnu tribute, and of the tribes of the steppe, these were also (but not entirely) bought within the fold. The Xiongnu Chan-Yu claimed in a letter to Emperor Wendi that he had united (by force);
"....all those who draw the bow" {steppes nomads}.
Trying to divide and conquer, Han Wudi dispatched emissary Zhang Qian to make an alliance with the disaffected Yuezhi tribe, enemies of the Xiongnu.
This is when the "Silk Road" was first discovered, when the envoy returned belatedly from his unsuccesful mission, yet told the Emperor of Chinese goods in far distant lands.
The Xiongnu taste for the luxuries sent to them by the Chinese under peace treaties, and the understanding it was essentially protection money from nomad raiding, is outlined in a letter the Chan-Yu sent to Wudi even in the midst of the open warfare between the Han and the Xiongnu; {from the Han-Shu}
QUOTE
--"In the south is the great Han; in the north is the formidable Xiongnu. The Xiongnu is the haughty son of heaven, who does not trouble himself about petty formalities. Now I wish to form a durable bond of union, by taking to wife one of the daughters of China. My proposal is, that China shall transmit to me yearly, ten thousand piculs of wine, five thousand bushels of millet and rice, ten thousand pieces of silk of various kinds, and other objects as in former treaties; then I will guarantee the exemption of the borders of the empire from raids and robbery."
By this time the Chinese had already turned from a political to a military option.
The latest overture was declined.
The breaking of the 'peace' and then victories under Emperor Wudi owe a great deal to the conservative policies and preparation of earlier conservative Emperors, i.e Wendi. The first half of the Western Han was however a period of crisis across the northern frontier.
For nearly 150 years the Han & the Xiongnu entered diplomacy as equals.
The Wudi-era wars between the Han and the Xiongnu saw much loss on both sides. Tens of thousands of casualties in individual battles with victories and defeats by each in turn. The Xiongnu however were driven from their Central Asian possesions and their leadership driven north during the reign of Wudi.
Much is said, and rightly so, about the effectiveness of a skilled mounted archer. It was these northern peoples 'Hu' that earlier had convinced one Warring States ruler, the King of Zhao, to adopt units of mounted archers from his peoples on the frontier, and even dress them in 'barbarian' clothes. While he was condemned for this by conservatives it was no doubt a good policy. By the Han period mounted archers, firing rearwards at a gallop, are commonly depicted in tomb lintels {below} and mounted bowmen included in Imperial Han Chinese armies. This is a style of mobile warfare associated with steppes warriors by Greek & Roman sources in the ancient world as it needs both excellent horsemanship and archery skills.










