Many myths exist about leather, and first and foremost many believe leather finds are rare in the archaeological record. This is utterly wrong; we have literally thousands of leather finds from Northern Europe just from the Dark- and Middle Ages.
As long as the ground is acerbic or anaerobic organic matter such as leather will survive more or less intact, even for thousands of years (other ways of preserving organic matter exist too of course, see for example the leather belongings of
Ötzi, which are about 5300 years old).
We have several examples of this from Scandinavian moors, especially Denmark (for example Thorsbjerg Mose, Nydam Mose and Illerup Mose) where our forefathers were quite forthcoming in sacrificing items aswell as people for us to study.
Other examples around Europe include suitable deposits such as Medieval wells, latrines and graveyards and we have thousands of leather finds from the Middle-Ages, especially shoes - the making of which leather seems the favoured material for (leather was used for other clothing too, of course, just not armor; it's cheap, easy to come by and excellent as protection against the elements).
