Scissor chair, birch.
A very practical, light yet durable folding chair. That kind of folding chair is easy to transport (folds flat) and makes every medieval event much nicer to stand (or seat...). You won't have to look for the place to sit on feasts- you can bring it with you!
Based on Savanarola type very popular in XVth century (Italian origin but can be easily found in museums all over the Europe. Common especially in Austria).