To Ur Is Human is a set of free wargames rules for Sumerian/Mesopotamian warfare. The game is designed to be played with 15mm figures on a grid.
ancients
Caesar’s Commentaries
Among his other talents, Julius Caesar also was a very good writer. The “Commentaries” on the Gallic and Civil Wars are classics of military literature, providing a unique insight into Caesar’s military campaigns. While it is true that there is an element of propaganda here, remember that history always is written by the victors. You can get the Commentaries in a free etext version here.
Ancient Wargames Rules
Nick Salmon offers a set of free wargames rules for ancients warfare. The author writes:
These rules can be used from antiquity up until the late medieval period, they depart from the norm in that they have no rigid turn sequence. Instead players take turns to command their troops until a situation occurs which occupies the commander allowing the initiative to pass to the other player. Combat results are handled by progressively worse morale and no figures are removed from the table. As befitting my age the rules are a bewildering mixture of imperial and metric measurements. Any areas not covered should be resolved with common sense or a die roll.
Ancient Wargames Rules
Steve Burt offers a set of free wargames for Ancients Warfare.
Minimal Melee Combat
Minimal Melee Combat is a set of free wargames rules designed to depict combat between sword armed adversaries.