The Flash is a DC superhero created by Gardner Fox and Harry Lampert for DC Comics in its golden age. Since then, he's become a fan favorite and staple of the DC Universe throughout all of his incarnations. From comics, TV, and movies, the Flash is always a loved and adored presence, bringing not only speed but a light-hearted nobility to whatever media he touches.
With such great speed that is derived from the speed force, the Flash is the host of many numerous and differing superpowers. However, one of his most famous is his ability to travel through time by running fast enough to break a time barrier. By doing this in comics, TV, and movies, the Flash has created multiple timelines and alternate universes, whether by accident or on purpose. Here are a few of those timelines, ranked.
7 Rathaway Timeline
Coming in at #7, the Rathaway timeline was created by Barry Allen on the hit CW show, The Flash. Yearning to find a way to beat Zoom, who was Team Flash's threat at the time, Barry travels back in time to learn more about the speed force from Dr. Wells, who was actually Eobard Thawne/The Reverse Flash in disguise. Stopping Hartley Hathaway from escaping Star Labs, Barry changes the timeline and throws some events out of order.
While establishing Hartley as a hero by the end of the climax of the two episodes it was featured in and introducing us to the concept of Time Wraiths in the show, nothing much else of importance occurs. Most of the timeline's effects or changes either resolve themselves or aren't mentioned again. It was a cool and short-lived little timeline that made for a fun couple of episodes, but that's it.
6 CW Flashpoint Timeline
After the events of Season 2’s finale, defeating Zoom and saving the day, Barry Allen had made a major decision. A decision to take control of his destiny with the power he was granted. With this, he travels back in time and stops Eobard Thawne from killing his mother, something he had stopped himself from doing in the past. This one change set in motion numerous changes to the Arrowverse for a short while.
While everything seemed better to Barry at first, after three months, he came to his senses and freed Eobard Thawne, begrudgingly allowing him to murder his mother. The timeline ranks at #6 because it lacks the nerve that the comic Flashpoint had. Any changes made to the timeline were reversed and anything that remained different was resolved within a season. Nothing too substantial and an honestly disappointing adaptation.
5 Vandal Savage Timeline
Sitting at #5 is the Vandal Savage timeline, a darker and more destructive look at what the CW could've been had it not been for Barry. This timeline was created by a Barry Allen who had traveled 24 hours into the past in order to stop Vandal Savage, who had killed all the other heroes in that world in a giant blast, with Barry as the only survivor.
While the timeline was resolved within a few episodes between the shows, it did give way for some pretty cool moments and character introductions, such as Hawkman and Hawkgirl. Vandal Savage proved to be a very fun villain to follow, and this timeline led into CW's Legends Of Tomorrow, which is full of shenanigans. Not something super substantial, but entertaining to see, at least.
4 Mark Mardon Timeline
The Mark Mardon timeline marks the first time that Barry Allen of the Arrowverse time travels, which makes this a moment of great importance for the series, earning it the #4 spot on this list. When Mark Mardon, brother of the show's first villain, kidnaps Joe West and sets off a massive tidal wave that presumably destroys Central City, Barry travels back in time a day, where he changes certain events and prevents this from happening.
The importance of this scene can't be understated in terms of the future of The Flash show. This timeline helped establish time travel as an important plot point going forward, showed the possibility of certain relationships that the show had teased, and proved how much of a hero Barry was in the face of adversity. While it's a small timeline compared to others, its impact is huge.
3 New 52
Created by Barry Allen of the comics in the aftermath of Flashpoint, this became the prime DC Universe for a while that found itself reset from the previous universe with minor differences here and there. This timeline gets a solid #3 on the list for its tenacity to try something different and for its importance to the DC Universe.
Introducing new concepts and tweaking origins to a new audience, Barry Allen created this timeline by going back in time and stopping himself from saving his mother. Giving the DC Universe such great storylines as The Court Of Owls and sleek new designs for all its heroes, the only thing holding back this universe is that it's the shortest-lived out of any DC era.
2 Flashpoint (Comics) Timeline
Flashpoint was one of DC's biggest and most game-changing events, as it reset the DC Universe with the introduction to the New 52. However, before we had the New 52, we had the twisted and crazy world of Flashpoint. It was created by Barry Allen when he went back in time to save his mother from death when he was a child. This set in order a chain of events that completely shattered the DC Canon we had come to know and pieced it back together in different and strange ways.
Coming in at #2 due to all the weird and interesting directions it took, Flashpoint introduced us to new and crazy subjects and characters, like Thomas Wayne Batman, who have persisted past the event. We saw a world that's under the war between the Atlanteans and the Amazons, with no Superman and no Flash. Eventually seeing that this new timeline couldn't remain, Barry goes back and merges with himself, preventing himself from stopping his mother's death at The Reverse Flash's hands and, in essence, bringing the world he knew back as a slightly altered New 52.
1 Post-Crisis Timeline
Taking the #1 spot on this list is perhaps DC's most famous and recognizable timeline/reality. It's known as the Post-Crisis Timeline, and it was formed in the aftermath of Crisis On Infinite Earths. This timeline was created by Barry Allen when he spent up all his energy and being into one last run, where he warned Batman of the upcoming threat of the Anti-Monitor, who threatened the very multiverse itself. Barry died shortly after, and because of Barry's sacrifice, the heroes were able to prepare and recruit, allowing them to win. A new Earth was created in the process.
This new timeline streamlined the DCU into one coherent universe that was deemed fan-friendly, allowing new characters to crossover and interact who couldn't previously. Many famous DC events and iconic moments were born from this timeline, such as The Death Of Superman and the death of Jason Todd. Eventually being tweaked and rebooted in the aftermath of the Flashpoint event, the Post-Crisis Timeline was the prime DC timeline for a number of years. It found itself to be many fans' introduction to the characters and worlds of DC Comics.