We know there were about a thousand towns of maybe two thousand people each, total two million population, and they had no war, no preparation for defense, nothing. That is a war zone now, so there has been no chance to learn any more.
We know nothing about the people or the culture, except that at some point they developed two distinctive languages: Babylonian and Akkadian. Everything before that, roughly 8,000 years, is lumped together and called "Sumer".
