Re: Previous 9 tails jinchuriki
I doubt the kyuubi had a host before.
If it did then the kyuubi would have already had to have submitted to previous person. Why doesn't it just submit to Naruto? It doesn't like being contained very well at all.
If it couldn't be controlled, then a ton of people would be dead, jinchurikis and villagers, and the kyuubi would be seen much to often to be considered a "natural disaster".
If Madara had the kyuubi before, he didn't keep it for his "Moon's Eye Plan" because either:
A) Tobi isn't Madara or
B) Moon's Eye Plan isn't really his final plan