What does Islam say about women being part of “war booty”? Are they treated as commodities, like wealth, ornaments and other valuable objects?

 Are they treated as such if the enemy are defeated? Do they automatically go from a free person to a slave? Are they only taken as spoils of war if not Muslim?

 Anyone know? I do remember this cropped up quite briefly (though off topic!) at Sonia’s blog but its not really something I’ve actively read or researched into.

So Islamically are women  of the opposition following defeat treated as “spoils of war”?