Captain Howdy said:
I really like Fields of Blood as a whole, and the mass combat rules are great. I don't have it in front of me right now, but I seem to remember some sort of system where each player contolled a realm in a campaign world, and the rounds went by like seasons, or something to that effect. A group doesn't even need a DM. That's a different game entirely, though. But the basic mass combat rules are really good, too. Check it out if you see it.
The game was (is) Birthright and it was published by TSR.
It is still alive at the Official fansite Birthright.net.
Here are various links that may prove useful/interesting.
The BRCS-playtest. The first 3.0 version attempting to be the sanctioned and “Official” Birthright 3/3.5 version.
http://www.birthright.net/download/brcs-playtest.zip
The sanctioned version of Chapt 2 (Bloodlines) {Basically the “Official” version of the chapter}
http://www.birthright.net/forums/index.php?act=Attach&type=post&id=25154
The most recent version of Chap 1 (all sanctioned except for the noble class, skill, feats and equipment).
http://www.birthright.net/forums/index.php?act=Attach&type=post&id=29614
From what I've read of Fields of Blood it seems awful similar (bordering on plagerism - but I can't really say that since I haven't read the book yet) to the Birthright setting.
The Birthright setting had the old gods dying and imbuing the mortal survivors with traces of their blood. Granting them abilities (blood abilities).
There was also a system of ruling with domain actions and regency (a system of collecting something from those being ruled which aiding in performing domain actions.)
There was also a system for handling mass combat, since war was a common theme.
Read the info from the links I've provided and let me know how "similar" Fields of Blood really is.
Note that the BRCS-playtest was first posted Feb 2003 (and announced on this web site by the way).
The rest of the progression to the current 'product' has been posted constantly.