So, apparently I was wrong about how old the concept of masked superheroes is. Just recently watched
Lost Hero of the Golden Age Episode 8: The First Super Hero (it's about nine minutes long), and apparently the early-Victorian 'prankster' criminal
Spring-heeled Jack was turned into a fictional hero by the penny dreadfuls of the time. One warning, the music in the video can be a bit intrusive at times.
I'm currently thinking that the Spring-heel'd Jack of Earth-3 is a succession of different men (and maybe a woman or two) using the identity for their own purposes, some of which are relatively heroic, and some not. This was probably also the case with the Spring-heeled Jack of Earth-2.
EDIT: The previous video got deleted and replaced with
Spring-heeled Jack: The First Super Hero, which is about twelve minutes long.