attackfish

Here's an odd thought- the war's been going on a hundred years, and possibly in that time there has been both a lot of soldierly death of noble sons and daughters of ancient houses, with the potential of wiping out long-established lines or breaking up power bases that might have rivaled the Fire Lord's over-arching hold. Some of that could be plain old attrition of the long war, and some of it encouraged and directed by a monarchy looking to solidify its hold over its territory rather than create new, powerful potential rivals by granting new land and old privileges to long-standing houses, as well as rewarding carefully-picked new loyalists. So maybe that's part of a large turnover in nobility.