They travelled from faraway lands, following a star to find salvation and pay homage to the man who would show them the way. But this was not Nazareth, and – this time, at least – there was no hint that he might be the son of God.

David Icke has learnt his lesson, and yesterday in the Croatian capital he even mocked himself for that disastrous 1991 appearance on Terry Wogan’s chat show, when he was ridiculed over claims that he was the son of God.

Icke’s reception at a packed Zagreb conference centre was Messianic in its fervour. Buzzing with anticipation, 1,300 people applauded with zeal as a giant screen above the stage showed a clip of the Wogan humiliation, and a booming voiceover declared: “Nothing has stopped him, and nothing will stop him.”

“You all thought he had disappeared,” one convert told The Sunday Telegraph. “But while you were buried in The X Factor, David was taking on the world.”

To whoops, cheers, and an audience of raised camera phones, Mr Icke, 59, strode on to the stage in a salmon pink shirt – paunchy and saggier than in his TV pin-up youth, but with the same piercing blue eyes and unmistakable grey mullet. “They all think I’m mad, you know,” he said, to laughter from the devotees seated in the dark conference hall. “But imagine being called sane in a world of such insanity? What a nightmare!”

Leaning forward in their seats, a crowd of teenagers, besuited businessmen, pensioners and middle-class couples, who had paid around 150 kuna (£17), hung on his every word. They listened intently as Icke began his intoxicating, eight-hour explanation of how we are all holograms; September 11 was “engineered terrorism”; the moon is a hoax; and the world is being controlled by a cabal of shape-shifting reptiles.

His tone was matey, his performance engrossing as he railed against “bleedin’ scientists” who think fluoride is good in water – when all it is really doing is “blocking your pituitary gland and keeping you in ignorance”. With PowerPoint slides and a whizzing stream of biological graphs and charts, he explains in pseudo-scientific terms how elves exist alongside sprites, and quotes Einstein, John Milton and Albert Camus. It is like being inside a Dan Brown theme park, set inside The Matrix.

One of the biggest cheers is for a joke about corruption among Croatia’s politicians – on the eve of today’s parliamentary election – and how absurd it is that they want to join the EU.

“We don’t trust politicians,” nodded Vanessa Valovicic, 18, an international business student who had travelled from the Adriatic island of Rab for the event. “When I first read his books, I was confused, and it took a while to make sense. But now I am excited by his ideas.”

Diana Dika, 43, an English teacher from Split, said her “eyes were opened” after reading Icke’s books. “It was like a puzzle coming together. It just made sense. Now I look at his website every day, and I share the information with my colleagues, friends and family. He warns about vaccinations because they are part of the control system, so just this week I argued with my doctor against having my daughter vaccinated. This is such a big moment for Croatia.”

That David Icke is circumnavigating the globe on a frequently sold-out world tour may well come as a surprise in the UK, given his gut-wrenchingly dramatic downfall. “They’re laughing at you,” Terry Wogan told him 20 years ago, “they’re not laughing with you.” But now it is Icke who is having the last laugh.

“People have suddenly picked up on this tour as if it is something new,” he told The Sunday Telegraph, in a series of emails. “But I spoke to 3,000 people in Los Angeles as far back as 2003. We are going to Wembley Arena next year for a simple reason – it has the capacity to meet the exploding interest.”

And the interest is, indeed, phenomenal. This autumn, Icke has spoken in 10 cities, across three continents. In New York, he was given a standing ovation by a sell-out, 2,100-strong crowd. Next week, in Amsterdam, he will talk to 1,750 people, while in Melbourne alone ticket sales racked up £83,000.

Through his website, you can download his £1.99 iPhone app, or buy DVDs of his performances for £29.99. T-shirts showing the cover of his latest book, Human Race Get Off Your Knees, sell for £15.

But T-shirts and ticket sales are small fry compared to the revenues generated by books. Since 1998, publishing industry analyst Nielsen calculates that Icke has sold 140,000 copies, worth over £2 million. They have been translated into 11 languages, and he sells “tens of thousands” in Germany, Romania and Sweden.

The boy from Leicester, first a professional footballer and then a sports presenter, has come a long way. In 1990, he had what he describes as his “awakening”, when a psychic in Brighton told him that he was a healer, placed on Earth for a purpose. Then came the infamous Wogan appearance.

He later told the television host: “I couldn’t walk down the street without people laughing at me. Going into a pub, there was uproar. A comedian only had to say my name to get a laugh.”

Icke retreated to the Isle of Wight, where he still lives, with his then-wife Linda and their three children. The introduction of psychic Deborah Shaw into the house completed what the media called “the turquoise triangle” – a colour Mr Icke wore for its “positive energy” – although Ms Shaw was kicked out when she became pregnant with Icke’s daughter.

Divorcing Linda, he remarried spiritualist Pamela Richards, but the demise of their union around 2007, and the subsequent costly divorce, is thought to have eaten into a large chunk of his fortune.

Indeed, there is no sign of vast wealth. His company generates only moderate revenues; he lives in an unassuming £115,000 flat in Ryde, where neighbours say he is “very pleasant” but not around much. Which, given that the world is hungry for his message, is hardly surprising.

Icke’s theories are an intoxicating mix of global politics, New Age rhetoric and “them-versus-us” conspiracy theories. He describes the press as “disrespectful, ignorant and stunningly ill-informed about the forces behind world events”.

“Icke is mad. Yeah, yeah; yawn, bloody yawn,” he told this newspaper. “My views are not well known except among those who have bothered to read my books and attend my events – that’s the trouble. I speak for 10 hours with no script and 1,400 images. Are all those people – especially when the talk is simultaneously translated through earphones – going to sit there all that time to listen to a nutter? Of course not.”

Dr Karen Douglas, a psychologist from the University of Kent who specialises in conspiracy theories, said that in an increasingly uncertain world, finding the comfort of an explanation becomes ever more important. “It’s dealing with their own lack of control over information, and empowering people to feel like they have the actual answer,” she said. “In the age of the internet, this all becomes easier to tap into.”

And she says that it is unjust to class everyone with an interest in conspiracy theories as being unhinged. “You can’t make the blanket assumption that they are all fruitcakes,” she said. “Most people are just looking for some kind of an explanation as to how they fit into the world.”

Mark Devlin, 41, a DJ from Oxford, travelled to Zagreb to see the show. And he admitted that at first he thought Icke was “a nutter”. “But I gradually became interested in his ideas, read his books, and it slowly slotted into place. I had what I call a conscious awakening.

“It’s human nature to question existence – why are we here, who are we? I’m sure people laugh at me behind my back, but I don’t care – and actually, more and more of my friends want to talk about this.

“People call David the loony lizard man, or an anti-Semite, as an easy way of dismissing him. They don’t want to question their own perceptions – it’s uncomfortable. But I think 100 years from now we’ll look back and realise that he was a major historical figure, of huge global importance.”

Outside, the crowds peeled off into the Zagreb night, their faces alight with revelation. Marko Tarle, 78, a former professor at the University of California, said he felt empowered by the experience. “It is amazing to know what is happening behind the curtain,” he said. “People deserve to know the truth.”