There are still a few rulesets out there for gaming with miniatures: though
Johnny Reb 3 and
Volley & Bayonet were designed with smaller figures (6 to 15mm) in mind, the principles are the same and can be adjusted to scale without too much problem. I'm not as sure about role-playing rules (which make me think more along the lines of
D&D etc) for historical-tactical, but I do know that small-scale "skirmish" games can come close and are popular.
@7thWisconsin may be able to guide you better there.