kryptonite and jimmy olsen first appeared on the adventures of superman radio show back in the early 1940s
flying superman started in the fleischer cartoons because he looked goofy jumping around
luthor did appear first named in a siegel and schuster action comics issue, but was a pretty different character from the one most recognized
anyway, glad the family finally saw some justice for jerry, the way siegel and schuster were treated by national comics after they were fired was just awful