God Will Know His Own is a set of free wargames rules for “Knight and Crossbow era Wargame Rules 1096-1590(or 1789) then into the horse and Musket era.”
Medieval Market Floorplan PDF
Dramascape has a free medieval market pdf.
Wars of the Roses Supplement for LoTR Strategy Battle Game
Here’s a Wars of the Roses supplement for the Lord of the Rings Strategy Battle Game. The original link has died. I’ve attached a copy below.
Bashing the Bishop Medieval Skirmish Rules
Here’s a fun looking set of medieval skirmish rules called Bashing the Bishop. The title tells you just how serious they are.
Tree of Battles 14th – 15th Century Wargames Rules
Tree of Battles is a set of free wargames rules for battles of the 14th to 15th Centuries.