Here are a set of rules from the man who is arguably the “Father” of American Wargaming, Jack Scruby: Basic Wargaming Rules.
Rules: 19th Century
19th Century Square Brigadier Rules
Ross McFarlane’s 19th Century Square Brigadier rules are designed for late 19th Century wargames on a square gridded battlefield.
Charge of the Light Brigade Rules
Charge of the Light Brigade is a set of free wargames rules by David Raybin for mid-19th century warfare. Raybin writes:
The rules (which have evolved over the last twenty years or so) were originally designed for conventions where players expected to be able to learn a game in under fifteen minutes and to start throwing dice almost immediately. Obviously, then, playability and fun are central to the rules. There is no strict ground or time scale. It is merely representational at best which, in truth, is all one can say about any wargame.
Early 19th Century Wargames Rules
The prolific Tyneside Wargames Club has produced a set of free wargames rules for early 19th Century Skirmishes.
The Immortal Memory
The Immortal Memory is a set of rule for refighting Trafalgar.