Who Started Fighting Crime First Clark Kent or Bruce Wayne?

Question

I know Superman predates Batman as far as first appearances in the comic books (1938 v 1939), but as far as the different universes go its not clear to me which character started vigilantism first. For example, in the new DC cinematic universe Superman started flying presumably after Bruce became the Batman. According to what has been said about the Dawn of Justice movie, Bruce will be the older Batman who has been around a while.

So who came first, Superman or Batman? I am more interested if they have mentioned this in the comics than the movie universes, but curious about both.

Answer 1

The comments cover most of the ground:

“I am more interested if they have mentioned this in the comics than the movie universes, but curious about both” — ha ha! Two universes! Yes, just the two.

Due to the nature of sliding timescales in comics, I'm pretty sure this is going to be near impossible to answer.

In any given universe, one or the other may have been operating first, and in various instances, it unambiguously was one or the other, in others, not.

So we're ignoring Superboy, then?

Here is where it becomes as unambiguous as things get. Speaking of the original, pre-Crisis Earth-Two, instances of Clark Kent and Bruce Wayne (and their Earth-One successors), we have Clark operating as the original version of Superboy well before Bruce Wayne is shown to have had any costumed adventures. While later versions of the characters have many permutations of this, including Clark never using his powers until maturity and Bruce taking the mantle of Robin in his youth, with the versions of the characters introduced first in the real world, Clark was first.