I'm not really sure if he created it or if it was a mutual Batman/Superman/you kind of thing, actually.
Technically speaking, Zeus has a tendency to...get around. A lot. He has the more famous demigod kids, like Hercules, and then the lesser famous ones like me. But there are dozens out there really. I only found out he was my father a few years ago. My mom didn't even know that he was a god. And then at first, I thought my powers came from him and they actually started to fade...until I realized I had powers of my own. So. There it is.