Real Cowichan sweaters are only knit by native women in the Cowichan Valley on Vancouver Island, Canada. The Vancouver Olympic Committee wanted 700 of them for the Canadian teams etc. Instead of having them knit in the Valley (everyone can knit if the need arises, so this could easily have been accomplished), the Hudson`s Bay Company got the contract to manufacture knock-offs, fakes in the Cowichan-style. There is a lot of controversy in the Valley over this issue. I spoke with several of the women who head-up the native knitting groups when I was at the Cowichan Fibre Festival and they were not even asked to put in a bid. It`s just the same as that shop in Edinburgh selling Alice Starmore designs without permission.
All that said, if you want to knit yourself a Cowichan-style sweater, not for resale, have a look at Priscilla Gibson-Roberts` Knitting in the Old Way (my edition is Nomad Press, 2004 but the book came out originally in 1985 from Interweave Press). The older sweaters were more tightly knitted than today and had mainly geometric motifs. These were like fair isle designs with thick wool, because a number of Scottish settlers showed the native women how to knit patterns and used the ones they were familiar with. The bird and animal motifs came later. The yarn was loosely spun but as it received fairly minimal processing except for a bit of washing (not enough to take away all the lanolin) it held together firmly. The sweaters were very warm, mostly waterproof, and wore like iron. I have a photograph taken about 1930 with one of my brothers wearing one. It was not new, so he received it from at least one older brother and maybe two, by the time I was wearing it in the 1950s, it had been through two more of us. So I was the fifth or sixth to wear it and then it was handed down to the next generation. We wore them for everything - in mud, brambles, in the woods, for chores, fishing. We probably smelt like unwashed wool by the end of the winter.
For yarn, most people use Buffalo, but homespun is great if you can get it. Consult with Ann and Angela about the closest Elann yarn - you never know what might be coming.
Salt Spring Island
(I was born in the Cowichan Valley)