Greetings Bill:
Hey, I'd like to take a stab at this one, since no one else has!
If this makes sense, I think "All of the Above" would be the correct answer!! "At the time of the Western Conquest", I bet you're talking about the Old West, that period from 1850 to 1900 (roughly). We know that leather used by book binders and other clothing industries had been dyed by leather producers in commercial lots, for some number of years. That would account for chaps, and other upholstery types of leather in the Old West! Yes, the leather was dyed by the manufacturer, prior to articles being made from it! The next level up, would be "harder" leathers such as those used for the making of Gun Rigs, Saddle Pouches, and such. If you can look at pictures of historical pieces, you will find fewer examples of dyed product...the color that you see in many of them, has been typically brought about by "patina" (events and substances that an article may have been subjected to in its lifetime, reacting with the tanning liquors, used to originally tan the leather). That being said,the large Mail Order Houses, such as Main and Winchester, Herman Heiser and others dealt with "ready made" orders by mail, in sizes, so you may think, that in order for them to fulfill those orders in advance, they had to have a standardized color. Also, if you think about it, Wagon Harness is another good example of items dyed by the leather manufacturer, and not by the maker! Most Harness was...black. Finally saddles...my opinion is that few were actually dyed by individual makers, or made with leather already dyed by the manufacturer! The exception to this would be the large mail order houses...
If you take a look in Packing Iron, which is a very good source for the History of Gunleather, you will find a few examples of gun leather that has been dyed...I'm thinking most of those examples fall into the category of the large mail order houses, but a very few will have been dyed at the time they were made! Remember, commercial dyes were VERY expensive and had to be shipped overland in glass containers, or the components of those dyes had to be assembled on site! Finally, there were other preparations, probably made by individual makers that were probably used...beef blood, comes to mind!
Now, just to ease your mind about "color" as a whole, in the product you may be making...don't fret it! It's a part of your fundamental creative processes to "create", so unless it matters, do it the way you want. I have made Royal Blue stuff in the past for customers...and although I had a different opinion, the customer really liked it, and that's what counts!
Man, it was a long way around the barn, but i hope it helped!
