Happy birthday, Hellblazer. One of the most significant ongoing comic series of modern times is 30 years old, and its central character John Constantine has well and truly earned his place in comics history. The first issue of Hellblazer was released with the cover date of January 1988, and it was eagerly anticipated by discerning comics readers who had become rather excited with what British writer Alan Moore had been doing on DC's Swamp Thing title.

In 1988, DC's mature readers line, Vertigo, had yet to be launched. But Swamp Thing and Hellblazer, together with the Grant Morrison-written Animal Man and, a year later, Neil Gaiman's Sandman, provided the template for the enduring brand, which this year marked its 25th anniversary.

John Constantine was introduced by Moore three years earlier in Swamp Thing #25, a wisecracking, streetwise British magician with a trench coat, ever-present cigarette, and snarky comment for any occasion. His look was based on the musician Sting, particularly his Satanic turn in the 1982 film version of Brimstone and Treacle, and his main role was to tutor the plant elemental in the supernatural landscape of the world.

When the time came for Constantine's own title, DC editor Karen Berger, who would launch the Vertigo line in 1993, had another British writer in her sights for the book: Jamie Delano. Delano had worked for Marvel's UK arm on original content, including the prose adventures of the criminally underrated Night Raven character and the science fiction weekly 2000 AD. In getting hired by Berger, Delano would spearhead the "British Invasion" that typified the early Vertigo years.

"Having muddled along for a few years writing the odd story for British comics, and proposing an original 'weird, dark superhero' series to DC, which was not taken up, I was surprised and a little daunted to receive a call from Karen one day suggesting I might like to come up with a proposal for a series, at that point untitled, featuring John Constantine," Delano recalled in a recent conversation with SYFY WIRE. "I came up with a few ideas for an initial run of stories and – with the benefit of what I imagine was a 'fair wind' from Moore – Karen was persuaded to take a chance on my dubious 'vision'."

For a British reader especially, if Moore's version of Constantine had been a welcome relief from the usual portrayals of "cor blimey, guv'nor" Dick Van Dyke-alikes who either lived in castles and stately homes or cute little mews houses in the middle of Olde London Town, then Delano's portrayal was an absolute joy.

Gaiman, who would soon write on the book, was thrilled at the British Invasion and new comics sensibilities the writers brought to American comics. "Alan Moore was English, Jamie Delano was English, Grant Morrison was Scottish … up to this point the portrayal of the UK in comics tended to be a mix of mountains and castles and interminable battles between mods and rockers, London portrayed as an enormous English village."

Credit: DC Comics

The first issue of Hellblazer began in an arresting if perhaps expected way … in New York, a man possessed of an unholy hunger starves to death even as he forces yet more sickening quantities of food down his throat. But by page four, and our first sight of John, we knew we were in for a rare and satisfying vision of Britain, possibly for the first time in American comics.

"The traffic is barely moving and the back of the taxi smells vaguely of last night's vomit," Constantine's narrative caption informs us, and he navigates teeming, rain-drenched, red-brick London streets lit by the "sickly yellow eyes" of street-lamps, streets that are "hardened arteries leading to the city's dead heart." Welcome to England, Americans! Hope you survive the experience!

Delano fleshed out Constantine's past … although his base of operations tended to be London, he was actually born and bred in Liverpool, in the north. He was a complex dichotomy, always looking out for number one, but unable to walk away from trouble. There was a fascinating, film noir-esque fatalism about him. If there was supernatural trouble, he was going to find it … or it was going to find him. And there was nothing he could do about it but go along for the ride. Constantine was cool and smart. He wasn't a hero, but was often forced into heroic acts against his will. His idea of a fight was to kick you in the balls and run away. You sort of wanted to be his friend, even though you knew his friends mostly ended up dead so Constantine could save his own arse.

"I suppose it was important to me that the character was human, and that – notwithstanding he operated in a supernatural genre – he primarily represented the concerns of 'real' people forced to struggle with the fact of their existence in a contemporary world," Delano said. "To a large extent it was inevitable, given my style as a writer, that Constantine would express and exaggerate aspects of my own voice and worldview -- so he was always going to be a flawed idealist with a veneer of cynical dark humor, who smoked too much and progressed through life with no clear sense of direction, flying by the seat of his pants, hedgehopping situations by instinct as they lurched up sudden from a low horizon."

British comics creator Bryan Talbot drew the Delano-written Hellblazer Annual #1, which told the story of one of Constantine's ancestors, the pagan king Kon-stan-tyn, but Talbot – whose current project is Grandville – has a part in the character's very genesis.

"Alan Moore and I once planned to do an urban horror comic called Nightjar, about a female British sorcerer," says Talbot. "I took Alan all around Pendle Hill in Lancashire for inspiration. The story never came off, though it was eventually published about 10 years ago by Avatar, but the basis of the character became John Constantine in Swamp Thing."

Although Constantine was officially firmly part of the DC Universe, by dint of his introduction in Swamp Thing, Delano never felt any pressure to incorporate him into the wider world beyond the core supernatural titles of Swamp Thing and, later, Sandman.

"Without a background in comics 'fandom,' the DC universe was largely irrelevant to me, and I had no desire to understand it, or for Constantine to play any active role within it," he says. "Now and then the 'crossover' specter raised its head and I needed to acknowledge Constantine's co-option into other titles — Swamp Thing and Sandman, for example — but these were rare distracting intrusions into Hellblazer's cosy isolation. Had I been asked to consider the universal continuity on any kind of ongoing basis, I would have been both unable and unwilling to do so."

Neil Gaiman brought Constantine into Sandman pretty early in the book's run, and wrote a one-shot story in the main Hellblazer title, the wonderfully melancholic "Hold Me," with rare sequential comic art by Dave McKean. Indeed, Gaiman's first actual comics work – though never published – was a John Constantine story.

Credit: DC Comics

"Like everyone else, I discovered the character in Swamp Thing," he says. "Then I promptly went off and wrote a Constantine script that never became a comic. It was my first experiment as a baby writer in how to write comics."

Indeed, borrowing a title from a piece by British punk poet John Cooper Clarke, "The Day My Pad Went Mad," the central idea for the never-seen Constantine story ended up in the mix for Gaiman's prose collaboration with Terry Pratchett, Good Omens, currently shooting for a TV series.

Gaiman's Hellblazer story appeared in #27. "Hold Me" was about Constantine wandering home after a memorial party for another fallen friend (the flamboyant Ray Monde in this case) and encountering the ghost of a homeless man. He says, "'Hold Me' is one of the comics of which I am most proud. I feel like I did something good there."

The story was inspired by a visit Gaiman made to the flat of a friend in Deptford, London, and the horrendous smell he noticed from a neighboring apartment. Apparently a homeless man had gained access to the flat to escape the harsh winter and died in there. But because of the intense cold, his body hadn't been discovered until the spring and the onset of warmer weather.

"Something about that stayed with me," he says, "something about the loneliness that must have been involved, about why no one cares."

"Hold Me" is as relevant today as it was almost 30 years ago, as is much of the social and political commentary that Delano not only didn't shy away from but often put front and center in Hellblazer – witness Constantine, captured by a group of yuppie demons, forced to watch through the night live footage of Conservative Prime Minister Margaret Thatcher storming to yet another election victory.

"I guess I did want to write a different type of comic: one that gained its impetus from the horror – largely social and political – shared and hopefully understood by both its characters and readers," says Delano.

"It was an interesting time for horror," says Gaiman. "In novels, Ramsey Campbell and Clive Barker were doing a very different sort of thing, using it like a crowbar to go at social issues, and Hellblazer was definitely a part of that."

Delano wrote the first 40 issues of Hellblazer, save for a couple of fill-in issues including Gaiman's "Hold Me" and a two-parter by Grant Morrison. The next 40 or so issues were written by Irish writer Garth Ennis, who delved deeper into Constantine's personal life, even presenting a rare happy time for the magician with a 40th birthday celebration party attended by the great and the good of DC's supernatural community (a note on age: In the Vertigo series, Constantine aged pretty much in real time. His birthdate is given as May 10, 1953, making him coming up for 65 this year).

Warren Ellis began what was planned to be a long-running tenure with Issue #134, after Paul Jenkins' run, but after 10 issues he left after a row with management over a script about high school shootings. Although written before the Columbine massacre, it was considered too on-the-nose, though it was later published in a Vertigo one-shot in 2010.

Hellblazer ran for 300 issues in total, with writers Brian Azzarello, Mike Carey, crime novelist Denise Mina, Andy Diggle, and Peter Milligan all exploring different facets of the character. Since 2011, John Constantine has been folded back into the DC Universe via the New 52 and Rebirth projects, and is firmly a part of continuity through his involvement with Justice League Dark.

Jamie Delano is currently exploring a prose fiction career, and his latest novels concern a character called Leepus living in a post-apocalyptic landscape known as Inglund. The books have a lot of synergy with his early Hellblazer work. Has he kept up with Constantine since departing?

"My relationship with Constantine was a difficult and intense one," he says. "Consequently I found it hard to maintain a monthly relationship once I'd abandoned him to the imaginations of others. I've dipped in now and again across the years, but inevitably we have drifted apart. I do believe one of the beauties of the complex character we have all jointly created is his ability to represent, through different aspects of his personality, a diversity of intellectual and creative vision."

He returned in 2008 to the character to write the graphic novel Pandemonium, with art by Jock, which was eventually released in 2010. "That story felt then like mine and John's swan song," he says. "Ten years on, I'm certain that it was."

But Constantine endures through the still highly regarded collections of the Vertigo title, the latest incarnations, and even the 2005 movie version starring Keanu Reeves, the recent Amazon Prime TV series, and the forthcoming animated show Constantine.

You never know where he's going to pop up next … even in the real world. Bryan Talbot recalls a story Alan Moore once told him. "Alan was in London while writing Swamp Thing, having a coffee in a café, when this guy walks through the door, suit, trench coat, cigarette hanging out of his mouth. He had short blond hair. It was basically John Constantine. He winked at Alan and went to the toilets in the back. Alan said he just got out of there."

So happy birthday, Hellblazer. The John Constantine we know and love from those days might be no more, but that sounds like an anniversary well worth raising a glass for. Knowing Constantine's parties, though, expect the unexpected when the doorbell rings.