Pelts are skins and fur gathered from slain animals. They are used to produce Hide Coats, Shoes, Shield, Hauberks and Platemail Armor.
The main source of Pelts comes from the Hunting Cabin as hunters will attack and butcher the Deer, Boar, Wolf and Bear in the area and skin them as well as harvesting Tallow and Meat.
Once the Hunting Cabin has been upgraded to Tier 2, the hunters will be able to construct hunting traps from Iron Ingots which will allow them to hunt for small game in an area, increasing the Pelt and Tallow yield from the hunter, but decreasing the Meat yield.
In the mid-late game, your main source of Pelts will shift from Hunting Cabin to the Barn where you will receive Pelts from every Cow that you slaughter.