User blog comment:Hatebunny/The DCnU, and why we have not made new pages/@comment-5135595-20120622063720/@comment-3361105-20120622130528

... why don't you READ flashpoint, then? (or at least the plot synopsis: http://dc.wikia.com/wiki/Flash:_Flashpoint).

Flashpoint is not one of the 52 universes. It's an alternate timeline. Like in Back to the Future II. Someone went back in time and screwed everything up. The Flash TRIED to put things back to the way they were, but he didn't get it quite right. Which means everything in the New 52 is slightly different from New Earth continuity.

So, to answer your question: some of the stuff that happened before flashpoint is canon, and some isn't. Read it to find out.