The need to tan leather started with the presence of the primitive men that by hunting the wild animals for food, they removed the hides and skin of the animals and used them for clothing, footwear and crude tents. The skins rapidly putrefied and became useless, so a method of preservation was needed.
It was until the medieval period that the process of preserving leather became an ART
Tanning leather = process to turn an animal hide into a leather in order to preserve it.
Since 1300 the process of tanning leather was developed in the Northern Italy, thanking the good position reach of water, which is the main component for the tanning process