Ok.
It was early game. I had cleared out the rebel stacks around my northern cities. I had taken Rhegium (sp?) and beaten back all the mini-micro stacks of Eperiotii in the boot heal.
I had a General family member, high loyalty, in command of my single maneuver army, dropped a siege on Tarantium (sp?) and next turn, my faction leader died and this general with rebel with my entire standing field army.
Is that WAD?
I'm sorry I can't post the save game. I have a habit of clearing out all the save games when I quit in a voodoo effort to prevent corrupted saves. So, it's gone :/
Didn't think I might need it until I decide to ask "wth?" on this.