Hard to say, actually. Although Kusari-Rheinland war was senseless, but generated a lot of fun and activity in the first couple of weeks, but later everything got into the very same drama and ganking each-other. The lack of solid RP-reasons, the attitude of players and et cetera left very bitter taste, so no wonder why things died and they died for good.
Bretonia vs Gallia war was too prolonged, but wasn't absolute trash and was good, comparing to this very same Kusari-Rheinland war. It had RP-reasons, the advantage of skill and number of players were more or less the same, jumping from one party to another from time to time, but it wasn't that bad. The whole minus was the feeling of artificial stuff, like "stuff happened which actually never happened in game", therefore there wasn't the real feeling of conflict, as for me.