In the Jungle is an interesting set of rules for conquistador vs aztec games. It’s played on a gridded board and is supposed to simulate a group of “lost” conquistadors trying to find their way to a temple without falling victim to sacrifice.
rules
French and Indian War Skirmish Rules – MAWS
Here are a basic set of free wargames rules for skirmishes set in the French and Indian War.
God Will Know His Own: Rules For Knight and Crossbow era 1096-1590 (or 1789)
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.”
Empire Knightly Orders Army Book For Warhammer
Here’s a fan-created Warhammer Fantasy Army book for the Empire Knightly Orders. As with the others in this series, it’s very well done.
Army Dudes Plastic Army Men Rules
Army Dudes is a set of free wargames rules for playing games with the classic green army men.