Student Council President
Even tho Skypiea was a while ago and comparatively early on in the series, I'll spoiler my response.In the Skypiea arc in the One Piece anime series, Enel, who is the main antagonist of that arc, says he's "god", is that true?
The simple answer, no. He's not god, he's just a delusional man with a lot of power. The more lengthy answer is that he's a resident of a far eastern sky island that he destroyed with his Devil Fruit power, Rumble-Rumble Fruit. He fashioned himself as a god and managed to convince some people with his powers and then took over Skypiea.
So yeah, he's just a dude who's gone mad with power and a formed cult, nothing more.
Hope that helps.