Gladius and Pilum is a set of free wargames rules for battles set in the 500BC to 500AD era. They’re designed for 15mm miniatures, with one figure equaling 50 men.
Rules: Ancients
By The Gods Ancients Warfare Rules
By The Gods is a set of free wargames rules for ancients warfare. The rules are relatively uncomplicated, but do have some modifications for “national characteristics.”
Bronzed Heroes Classical Warfare Skirmish Rules
Bronzed Warfare is a set of free wargames rules for skirmishes in the classical bronze age.
Death On The Seas Ancient Naval Rules
Death on the Seas is a set of free wargames rules for ancient naval warfare. Also, Death On The Seas ship appendix.
Thumbs Up, Thumbs Down Gladiator Rules
Thumbs Up, Thumbs Down is a set of free wargames rules for gladiatorial combat. The rules are designed for up to ten players.