Greetings folks, I am trying to identify a cartoon I watched in the early 70's. All I remember is a Prince character and that he wore a medallion with the Letter P. I'm pretty sure it's not Prince Valiant or Battle of the Planets. Any help would be greatly appreciated.

Prince Planet. A great classic show. It features some really old Japanese animation, before they really became skilled, but still, Prince Planet is right up there with Astro Boy. Here's a peek at the opening with a really, really bad song.

YouTube - Prince Planet