A really important factor in the world is the weather, the weather affects us how we dress, how we eat, war on others, and the possibility of robberies, trades, commerce and most other stuff. Though the aspect of weather is often forgotten in terms of roleplay games. The heroes on their mighty quest is rarely forced to hide in cover in a cave or seek help from the rain at a stranger’s house. Both heat and cold weather along with rain, snow and drought, can all affect the game and how it ends out.
In medieval times when the weather got colder, truce was made and people struggled to keep their warmth.
In a cold environment, you basic need is four things. 1. Food, 2. Water, 3. Shelter, 4. Warmth. Staying out in the wild was only possible for a short period of time, because food is difficult to gather, water is often frozen and to get shelter and warmth, there would be problems with setting up a solid shelter and often were fire not a possibility because of the flammability of the tents and the rather smoky nature of a bonfire.
Normally this was solved using three layers of clothes, inner cloth was either made of silk, could you afford it, or linen, this was to protect the skin towards the rough nature of the second layer. A thick layer of wool was added to keep the body warm. Even when wet wool would keep the body at a tolerable temperature. And the outer layer was treated wool making it water resistant. This treatment would affect the heating quality.
This apparel was worn around the clock, all day, inside and outside, even slept with the really cold nights. This is because of the bad heating properties.
Vikings had their livestock in the house to share body warmth, and a hearth in the center, to act as both heating and cooking place. In longhouses this was found as the most efficient way to keep the warmth at winter.