Current thought on leather armor from the history of Europe goes like this: there are thousands of examples of leather belts, shoes, pouches, tack, vests, and other leather products found all over archaeological sites throughout Europe and the Mediterranean. However, not one single example of leather armor has ever been found at sites of battles, stongholds, armories, burial mounds and graves, or anywhere else. The only leather armor that's been found are padded jacks that were worn under maille, and a few kid-sized stuff that was obviously made as a toy for children.
That's it. Leather armor is an invention of Dungeons & Dragons and fantasy literature. Don't get me wrong, I love leather armor. I wear it when I fight and make a lot of it. But don't kid yourself - what you're making is "historically styled", not "historically accurate".
Ug, sorry about the rant...