I knocked up a rule set as an exercise in turning the Rethemi Civil War into a board game. I used the core of the 'One-Role Engine' found in Reign and used for it's 'Company' Rules, which is to say 'role-playing' an organisation or faction.

I'm not certain they'd work as a PBEM but it was intended to be GM free in a face-to-face game. Though there is a Cyberboard Gamebox to go with them that was intended to allow 'play-by-projector' not PBEM, with the cyberboard board, cards and tokens replacing the physical game components I'm not up to producing.

I've tried to attach the pdf but I get a message that they are too big. If anyone is interested in reading them, PM me.