Well, there has been som discussion in random topics, but i dont think there has been a thread dedicated to this duscission yet.
Anyway, in ep 55 we hear Yama-ji (the first captain) say that he started the academy where all the shinigami train. So obviously tehre wasn't ALWAYS a SS (im refering to the SS we know, but the ordinary souls that live outside the noble area) or shinigami.
Now, given how slowly the SS residents age, and the age of the first captain, i'd say that he established the academy 1000+ years ago. Im assumming that Soul Society itself has been around since the begining of time or something, but does that mean the shinigami have been around that long as well? or was Yama-ji the first one?
Heres how i see it:
Case 1: Shinigami have been around forever, and yama-ji just organized them and created the academy.
Case 2: Shinigami came into existence when the academy was created 1000 some odd years ago. In this case, the hollows must have come into existence just prior to the creation of the acedemy, thus forcing SS to do something about them. Here, im assuming some cosmic disbalance or something resulted in the creation of the first hollows. Before that, everyone was just a soul.
Case 3: Hollows have been around forever, and there have always been people fighting them (just random people, but not shinigami). Yama-ji created the academy to organize an army/militia of sorts, and thus the shinigami were born.
Lets hear what you guys think about it all. Discuss away!