Crisis on Earth-X: The comics history of this Arrowverse crossover event

With Crisis on Earth-X slated to take over the CW, how will it compare to the comics?

Monday night begins the Arrowverse’s anticipated, four-part event “Crisis on Earth-X.” This brings the cast of Arrow, The Flash, Legends of Tomorrow and Supergirl together to fight the enemies of Earth-X, which features some evil doppelgangers and other villains that will look to thwart everything.

“Crisis on Earth-X” will take idea and concepts from DC Comics and turn them into a reality. What will these be, however? Let’s take a brief look:

If you followed the past few seasons of The Flash, you will know that multiple universes exist. Probably more than anyone can imagine in the Arrowverse. Earth-X will be the latest that’s added to the mix.

Created in 1973, Earth-X’s stands out, as this parallel universe saw the Nazis win World War II. This happened when President Franklin Delano Roosevelt passed away and allowed for Germany to overtake the war, winning and continuing a dominance that lasted for decades.

Earth-X featured the Freedom Fighters, which viewers will get a glimpse of in “Crisis on Earth-X,” as The Ray will be introduced. In this 1973 comic, the Justice League of America and Justice Society of America helped the Freedom Fighters fend off the Nazis.

There were more Freedom Fighters than just The Ray, as Uncle Sam, Black Condor, Doll Man, Human Bomb and Phantom Lady were part of this team. Whether any of them appear remains to be seen. Given the magnitude of this event, potentially expect someone to make a surprise debut.

Unlike the comics version, “Crisis on Earth-X” will see the titular characters of Green Arrow, Flash and Supergirl take on villainous personas. That means a darker version of Oliver Queen, something that hasn’t been seen in the six years of Arrow.

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“Crisis on Earth-X” is about to begin, so enjoy what’s to come.