I really don't think you know for sure where the hair actually comes from...and more likely than not it will end up being Chinese hair anyway...
There is a LOT of marketing/hype going on with badger knots - and even if you get a knot by a supplier you love today, it doesn't mean you can get the same knot from the same supplier tomorrow.
That's why I stick these days with suppliers, who actually describe their knots and/or have a good reputation
Most correct my friend, let me spill some information in
general terms...
The badger hair from all of the artisans I know is exclusively Chinese, however theirs is different to most if not all of the American market and it is why their brushes are so good.
The first important distinction is between buying already set knots and buying
batches of badger hair that you can have set into knots based on your specifications in China, or tied and sent to you for you to set yourself. Already set knots are a dime a dozen and most often contain all the hair lots that have been passed in by the big 2 players (Isle of Mann/Germany), this hair is then sold to wholesalers who bleach and treat the tips, set in glue and offer wholesale boxes of 24,48, 72 badger knots that are bought by retailers to sell in US online retail stores. There are 2 or 3 suppliers in this wholesale game who onsell to other wholesalers which is evident as we see the exact same grade of mixed hair in just about every knot. Knots labeled as 'manchurian' or 'high mountain white' are a mix of hair from different sources which is treated, this is why a knot from the Isle of Mann is of a substantially better quality than a knot bought in the US for $50 or so.
In regard to the source of the hair when you buy
lots of badger hair (not set knots, weights of graded hair) the sellers provide extensive information and pictures in a bid to garner new business including sending tied knots of grades for evaluation. Making contact with these parties in China is very difficult due to existing relationships and the highly profitable wholesale market selling already set knots. Most of the sellers if you do locate them will not do any business with you due to the two main players. Their are two artisans in the US who have managed to connect with these wholesalers and are subsequently known for their grades of knot, quite understandably these two artisans are guarded to the point of paranoia about their relationship and source - it is the cornerstone of their business.