Dispelling Some Myths: Chinese Ironworking
Hosted by the actor Danny Trejo, the US television series 'Man at Arms: Art of War', brought together martial arts experts and master blacksmiths to recreate some of the most popular weapons from movies, television shows and video games. The show is clearly intended to be entertaining, hence the graphic demonstrations of the featured weapons’ capabilities. Moreover, the addition of master blacksmiths to recreate the weapons provided useful insights into how they might have been forged. All good. Yet, at its heart this is supposed to be a factual documentary so, as keen historians, we are always alert to any claims made that seem, well, misleading.
Bold assertions Episode One of Season One, titled 'The Weapons of Kung Fu', focused on two ancient Chinese weapons, namely the 'Wind and Fire Blade' and the ji, a polearm. In the introductory sequence, in the so-called 'War Room', publisher of Kung Fu Tai Chi magazine, Gene Cheng, stated:
'China was way ahead of the rest of the world when it came to metallurgy.'
Blacksmith Kerry Stagmer, of Baltimore Knife and Sword, agreed: 'They were certainly mass-producing weapons in iron far ahead of anybody else. When so many other countries were struggling with just figuring out how to make it [iron] in the first place they were mass-producing. They were mass-producing weapons for armies with thousands of people in it. A big advancement over bronze.'
These are bold claims that, at best, are not entirely the truth. From the moment China's economic 'Open Door Policy' shifted to encouraging and supporting foreign trade and investment, starting on its path to becoming 'The World's Factory', access to and the study of Chinese history by western academics was notably improved. Consequently, documentary makers had a wealth of exciting new material to explore and broadcast to audiences in the West. This resulted in several factual TV documentaries revealing ancient Chinese technology in which it was enthusiastically asserted that China was far more advanced than the rest of the world. Understandably, given the premise of these documentaries, the focus on Chinese technological 'firsts' effectively ignored contemporary or competing innovations outside China to create a somewhat biased view. Such unbalanced and misleading claims are so frustrating, especially when one actually compares Chinese and European historical achievements. So, when it comes to the history of iron working, were the Chinese as advanced as the 'Man at Arms: Art of War' show implied?
The Iron Age In a subsequent piece to camera Cheng stated: 'China actually has the oldest metallurgy. They moved out of the Bronze Age into the Iron Age around about the Spring and Autumn period, some 3,500 years ago.' Not quite. The Spring and Autumn period , which roughly corresponds to the first half of the Eastern Zhou period, was from approximately 771 BC to 476 BC. At its earliest, therefore, it was about 2,800 years ago. Cheng effectively introduced a not unsubstantial error of nearly 700 years; still '3,500 years ago' does sound more impressive.
Leaving the pedantry aside, the Iron Age is conventionally defined by the widespread replacement of bronze weapons and tools with those of iron and steel . That transition happened at different times in different places, as the technology spread. Mesopotamia was fully into the Iron Age by 900 BC. Although Egypt produced iron artefacts, bronze remained dominant until its conquest by Assyria in 663 BC. The Iron Age began in India about 1200 BC, in Central Europe about 600 BC and 300 years later in China (ca. 300 BC) . This means China was somewhat behind in adopting iron, and it is still debated whether the technology of bloomery-based ironworking ever spread from the Middle East to China. Rather, in an example of 'simultaneous invention' , it is just possible that Chinese ironworking developed independently.
Cast iron Returning to the show, Cheng then stated:
'The Chinese were the first to create cast iron. Now cast iron is a stepping-stone to steel, and the Han Dynasty, which is about the time of Christ, developed massive blast furnaces that could raise the temperature of cast iron hot enough to start creating steel. And that was centuries before any other culture developed it.' Once more Cheng’s claims are confusing both on the timing of these developments and his implication that the advance from cast iron to steel was a simple step achieved in a short period. The history of Chinese metallurgy is neither simple nor as unique and ground-breaking as the show would have us believe.
The earliest cast iron artefacts, dating to 5th-century BC, were discovered by archaeologists in what is now modern Luhe County, Jiangsu in China. Compare that date with the introduction of iron working to Greece in the 10th-century BC (see InfoBox right) and one begins to see that Cheng’s claim that China’s iron industry was 'centuries [ahead] of any other culture' does not stand up to scrutiny. That said, around 500 BC metalworkers in the southern state of Wu achieved a temperature of up to 1130 °C which is hot enough to use a hearth as a blast furnace. At this temperature, iron combines with 4.3% carbon, melts and in its liquid state it can be cast in moulds. This method of manufacturing objects is far less laborious than individually forging each piece of iron from a bloom as would have been the case in Iron Age Europe.
According to Wagner (1993) cast iron was subsequently used in ancient China for warfare, agriculture and architecture . The claim regarding its use in warfare is surprising, and debatable, since cast iron is rather brittle and unsuitable for striking implements. It is far more likely, therefore, that cast iron was largely employed for non-military uses, for example by Chinese farmers.
If iron ores are heated with carbon to between 1150°C and 1200°C, a molten alloy of about 96.5% iron and 3.5% carbon is formed. This product is strong, can be cast into intricate shapes, but is too brittle to be worked. If, however, cast iron is heated in air for several days it is decarburized to remove most of the carbon to become wrought iron or a form of steel. The process is time and resource (fuel) consuming so the vast majority of Chinese iron manufacture, from the late Zhou Dynasty  onward, was of cast iron .
Toward the end of the Zhou Dynasty iron working methods spread northward. By 300 BC, about 150 years after the La Tène culture first appeared in Europe, iron became the material of choice throughout China for most tools and weapons. A mass grave in Hebei province, for example, dated to the early 3rd-century BC, contains several soldiers buried with their weapons and other equipment. The artefacts recovered from this grave are variously made of wrought iron, cast iron, malleable cast iron, and quench-hardened steel, with only a few, probably ornamental, bronze weapons.
Having been rather dismissive of the show’s claims it is worth noting that Cheng was correct when he said 'massive blast furnaces' were developed during the Han Dynasty (206 BC to AD 220). The government of the period established ironworking as a state monopoly and built a series of large blast furnaces in Henan province, each capable of producing several tons of iron per day. By this time, the 1st-century BC, Chinese metallurgists had discovered how to refine molten pig iron. By stirring it in the open air until decarburized it could be hammered to produce 'wrought' iron, or an early form of steel . In modern Mandarin-Chinese, this process is now called chao, literally 'stir-frying', while pig iron is known, in translation, as 'raw iron' and wrought iron is known as 'cooked iron'.
Contrary to the assertions of this episode of 'Man at Arms: Art of War', one final example may be valuable. According to Needham (1986), the production methods of creating a form of high-carbon steel known as Wootz was an idea imported from India to China by merchants no earlier than the 5th-century AD . So, the Chinese were no more innovative in iron making than many other cultures across the globe. This is not to dismiss China's ironworking methods, innovations or practical applications, but merely a reminder to place the country's achievements in a wider, world context.
1. The period's name derives from the Spring and Autumn Annals, a chronicle of the state of Lu between 722 and 479 BC, which tradition associates with Confucius (551 - 479 BC).
2. Williams, D., (1867), "The Iron Age", Iron Age [weekly journal], New York.
3. Tylecote, R.F., (1992), A History of Metallurgy, Second Edition, Maney Publishing [for the Institute of Materials], London.
4. The concept of 'simultaneous invention' (more popularly known as 'multiple discovery') is the hypothesis that most scientific discoveries and inventions are made independently and more or less simultaneously by multiple scientists and inventors. As an example, stepped pyramids have been built by ancient peoples in South America, Egypt and Asia. It is probably safe to say that these people never met being separated by time and distance. What they share, however, is the ability to come up with similar solutions to similar problems independently (and all without 'Alien' involvement).
5. Wagner, D.B., (1993), Iron and Steel in Ancient China, BRILL, p. 408.
6. Riederer, J., & Wartke, R-B., (2009), "Iron", Brill's New Pauly: Cancik, H., Schneider, H. (eds.).
7. “Noric steel” is named for its place of origin, namely Noricum, an Iron Age kingdom located in modern Austria and Slovenia.
8. Craddock, P.T., (2008), "Mining and Metallurgy", in: Oleson, J.P. (ed.), The Oxford Handbook of Engineering and Technology in the Classical World, Oxford University Press.
9. The Zhou Dynasty (1046 BC to 256 BC) followed the Shang Dynasty (1600 BC to 1046 BC) and preceded the Qin Dynasty (221 BC to 206 BC). It lasted longer than any other dynasty in Chinese history (790 years).
10. Needham, J., (1986), Science and Civilization in China: Volume 4, Part 3, pp. 197, 277 and 563.
11. Needham, J., (1986), Science and Civilization in China: Volume 4, Part 1, p. 282.