As the The Dark Age of Comic Books moved on, DC Comics noticed they were publishing several series that weren't just dark, they were mature — with complex, thinky, often philosophical stories and deep, complicated characters, by names like Alan Moore, Grant Morrison, and Neil Gaiman. Thus, to separate these from the "normal" DCU fare, they created the Vertigo Comics imprint.Many of these were remakes of old DCU properties, given new life through clever writing. The Sandman, Animal Man, Doom Patrol, and Swamp Thing are probably the exemplars here. It seemed the rule was "The more obscure, the better"; series like Brother Power: The Geek, a two-issue Totally Radical attempt from the '60s to appeal to the "hippie" market, were brought back as dark, edgy romps.This had the knock-on effect of pretty much excising certain characters from the main DCU, for fear that a John Constantine and Batman crossover would encourage little kids to pick up Hellblazer. This meant that certain comics, though still technically part of the DCU, were unable to do "proper" crossovers or acknowledge that connection directly. This was relaxed occasionally for one-panel cameos (Constantine in Hitman), characters whose comics have ended (Daniel from The Sandman appeared in JLA, while Animal Man and the Doom Patrol have come back to The DCU full-time) and characters who have always straddled the divide between the two (the Phantom Stranger, Zatanna, et al). DC's 2011 partial Continuity Reboot brought several characters like Constantine and Swamp Thing back into the main DC continuity fold. The Vertigo-only Hellblazer continued to be published separately until issue 300 in 2013, when it was replaced by a main-DC-universe Constantine title. This left Vertigo proper no longer publishing any ongoing title featuring characters originating in the DC universe.Over the 2000s, however, the focus of the imprint had gradually shifted from its original shared-universe titles to creator-owned original works. These are still often in the horror/fantasy genre. 2009-11 saw an unsuccessful attempt at genre diversification with a series of "Vertigo Crime" graphic novels, although a number of the published titles retained supernatural elements and one of the first to be published was a Hellblazer special.
Some of the best-known series published by Vertigo include:
Some Vertigo series are technically part of The DCU, due to using DCU characters, and Word of God says the shared universe titles like Hellblazer and The Sandman ARE part of the mainstream DCU. However, not all of them are always canon for the DCU characters, and some of them effectively take place in a world of their own. These include: