...where did everybody go?

Since Isherwood didn't make a post today, I'll man it again.

Today, write about a conflict that has been going for very long - perhaps, since the beginning of time. Who the warring factions might be? Are they the same people who started it, or those who inherited the burden of hatred? What drives them still?

P.S. If that's too easy or too abstract for you, let me know.