Material Matters: Wool
Woollen fabric is older than civilisation itself and these days it accounts for about $80 billion USD in retail sales per year. The fibre’s ability to absorb and release moisture has helped it become a staple textile in the wardrobes of athletes, soldiers, fashionistas and even astronauts. The most common kind of wool comes from the fleece of sheep, but other animals such as goats, muskoxen and rabbits produce various forms of wool in smaller quantities, making it one of the most diverse textile fibres in the world.
People have been wearing the skin of animals since long before any record of humanity began. Hunting wild sheep taught them the value of fleece as insulation but the short bristly hair of the free-range animal was far from what we know now – today’s fluffy fleece being the result of selective breading and more recently of genetic engineering. When people began to domesticate sheep around 10,000BCE they started to recognise the value of the animals beyond merely slaughtering them for meat – they could be milked and their fleece they shed could be woven into cloth. Originally, wool production was more common in colder areas, as the sheep in those climates grew more fleece to protect themselves from the weather – making it easier to use. Archaeological evidence from Iran suggests that the woolly sheep emerged around 6,000BCE and they were then introduced into Europe 2,000 years later. As civilisations grew and spread, so too did the wool industry.
The earliest production of woollen cloth consisted of subsistence farmers weaving hand-spun fibres into crude, but effective cloth. The technology of spinning and weaving slowly developed and throughout the ancient world dominance of the industry would shift from one civilisation to another – the whole time remaining a highly lucrative business. In many regions, such as Britain, wool remained the standard cloth for clothing until relatively recently when colonialism and global trade presented alternatives – although the colony set up in Australia relied predominantly on wool for trade, leading to Australia’s modern day dominance of the industry (currently around 25 percent). Even with the modern technology and our ability to synthesise materials, we still don’t have anything that can compete against wool.
One of wool's biggest selling points is its incredible ability to reduce heat transfer. That means that if you wear it when it’s cold outside the heat doesn’t escape the fabric – on the flip side if it’s hot outside then less heat can get in, meaning a thin, loose woollen garment can actually stop you form overheating. Not only that but it stays warm when it gets wet, it’s elastic and is highly unlikely to ignite when comes in contact with fire. Many of the beneficial qualities of wool come from the structure of the fibre. It has lots of little waves, or crimps, so it creates a thick fabric filled with little air pockets. The weave remains strong thanks to the tiny barb-like scales on the fibre’s surface that grip firmly to one another. Aside from being spun into yarns and woven, the fibres can be hammered and matted together to produce felt.
You might assume that the oldest form of woollen footwear would be the sock, which dates back to 11th century Egypt with the first recorded examples of knitting – in fact, the oldest known form of woollen footwear popped up around 1500 years ago on the Great Steppe, which was a kind of boot formed out of felted wool. Throughout 12th Century Central Asian and Caucus regions, people wore decorative woollen socks, which were sometimes fitted with a leather sole. Moving into Byzantine times, woollen elements of traditional Greek shoes were predominantly decorative, which has been the main use of wool in footwear until more recent times.
Unlike most of the other materials we see on modern sneakers, wool didn’t arrive on the scene as some kind of technological breakthrough or in part of a performance arms race. You could consider it to be one of the world’s oldest performance fabrics, which would explain how athletic footwear producers got their hands on it in the first place. Alongside their sneakers, brands like Nike, adidas, ASICS and Brooks were outfitting athletes with woollen jerseys and Melton wool jackets, in early days it just made sense as a warmer alternative to canvas, but was more elastic so it couldn’t support the foot in the same way. Tightly woven woollen fabrics slowly made their way onto running styles as an alternative to mesh, surrounded by leather panels for stability.
The recent knitted construction takeover – with technology like Flyknit and Primeknit dominating the sneakersphere – has just been begging for a wool revival. Not long ago adidas released a whole collection of woollen Primeknit styles in their ‘Winter Wool’ range. Converse have been working together with Woolrich to make buffalo plaid and tartan to wrap up their Chucks, while Jordan Brand recently dropped a woolly Jay 12 to keep the winter blues at bay. You can see Nike collaborating with the history-steeped Pendleton Woollen Mills, who are lending their traditional patterns to brighten up some sneakers, and for the ladies Nike have a recent collection which pairs wool with its traditional counterpart, leather.
It might not be the obvious material when you’re thinking of sneakers, wool has just nestled into the fabric of the industry without fanfare or fame. Perhaps we have such an intrinsic reliance on the age-old fibre that we don’t really notice it but it’s nice to know we’ve got it there when we need it – now and for many years to come.