Arctic hunter-gatherers were advanced ironworkers more than 2,000 years ago
Hunter-gatherers who lived more than 2,000 years ago near the top of the world seem to have conducted ironworking activities as advanced as those in agricultural communities far to the south.
Excavations in what is now northeastern Sweden revealed old kilns and fire pits that hunter-gatherers used for metalworking. A mobile lifestyle did not prevent hardy groups based in or near the Arctic Circle from organizing large-scale efforts to manufacture iron and craft metal objects, says archaeologist Carina Bennerhag at Luleå University of Technology in Sweden and colleagues. In fact, hunter-gatherers who for part of the year moved over cold, wooded areas with lakes and swampy spots apparently exchanged resources and knowledge related to metallurgy, extraction of metals from ores, the researchers report in December Antiquity.
Ancient hunter-gatherers in two Swedish places “probably made more iron and steel and were more socially organized and sedentary than we previously thought”, says Luleå archaeologist and co-author Kristina Söderholm.
Groups must have settled for significant periods of time in places near important resources, such as ore for exploration, wood needed to make charcoal and clay, and stone needed to build kilns and fire pits used in iron production, the researchers say.
Many scholars consider ironworking to be an invention of large agricultural communities in southwest Asia more than 3,000 years ago (SN: 22/8/13). From there, this technology has generally been considered to have spread elsewhere, and was eventually adopted in simplified forms by humans in northern Scandinavia and other Arctic areas between 700 and 1600 AD.
But that view has been questioned in recent years. More and more evidence suggests that ancient technologies, including metallurgy, were mastered relatively early on by small-scale societies, says archaeologist Marcos Martinón-Torres of the University of Cambridge, who was not part of Bennerhag’s team.
“This study is particularly insightful because the metal is iron, usually considered a more challenging metallurgy than copper or gold; the creators are hunter-gatherers, historically they are assumed to use only basic technologies; and the site is in a region largely ignored in technology history, ”he says.
Bennerhag first directed excavations at a site called Sangis. Investigators discovered a rectangular iron smelting furnace consisting of a stone slab frame with an open side. A clay shaft was built inside and partly on the frame. Holes in the frame acted as inlets for air that was blown on burning coal inside, probably from bellows placed on flat stones, the researchers say.
By-products from heating iron ore at high temperatures and residues of a ceramic wall cladding were found inside the furnace. Radiocarbon dating of kiln remains indicates that iron production took place between around 200 and 50 BC.
Areas that hunter-gatherers occupied about 500 meters from the kiln contained ceramic fragments and other material that were dated to between about 500 BC. and 900 AD. There, researchers found several iron objects and others made of steel, a bronze buckle and metal waste with copper drops on the surface, which indicates that various metals were manufactured at Sangis.
The bronze buckle’s shaping technique and decorative style are similar to metal objects found in places for hunters and gatherers in northwestern Russia that are dated to as early as about 2,300 years ago, the researchers say. Knives and other metal objects found at Sangis contained two or more layers that had been welded together in an expert manner and, in some cases, subjected to one of two types of heating processes to improve their strength.
Excavations at a second site, Vivungi, revealed the remains of two iron smelting furnaces that contained iron ore, by-products of iron production and fragments of ceramic wall cladding. Iron production at Vivungi started around 100 BC, the researchers say. Vivungi gave no evidence of fire pits where iron was further purified.
Radiocarbon dating of animal bones found near the Vivungi kilns indicates that hunter-gatherers repeatedly occupied this site from around 5300 BC. to 1600 AD.
Evidence of iron production in southern Scandinavia more than 2,000 years ago already existed. So discoveries of similar old ironworks further north make sense, says archaeometallur Thilo Rehren from the Cyprus Institute in Nicosia, who did not participate in the new study. Preliminary work indicates that iron production also began in East Asia more than 2,000 years ago, Rehren adds.