'Twitter is a playground and the website is the office," says Reverend Stuart Campbell, when asked whether he is a wind-up merchant.

Campbell is the founder of Wings Over Scotland, a controversial pro-independence site that gets an astonishing 4.5 million page views a month.

Born in Stirling, he moved to Bath in 1991 for a job at a computer magazine and became a notorious reviewer of video games. He has lived in Somerset ever since.

The 46-year-old is also a long-term supporter of Scottish independence, but the issue only became pressing for him when the SNP's landslide Holyrood victory in 2011 made a referendum a certainty.

Wings, known for its abrasive take on Scottish politics - one Tory MSP was described as "fat troughing scum" - was started six months after Alex Salmond's historic victory.

"I was looking around for Scottish politics websites to follow ... and they weren't doing the job," he explains, sitting in a friend's house in Keynsham, outside Bath. "It became fairly rapidly obvious that nobody was doing the thing that I thought needed to be done."

Other than giving readers what he describes as the "facts" about independence, Wings also attempts to shine a light on newspapers' alleged bias.

In a podcast interview last year, Campbell said he wanted to "shame" the mainstream press and ensure newspapers did their job in a "more even-handed way".

Does he think newspapers have a duty to be even-handed? "No is the short answer. They don't have a duty to. I think they should be."

Newspaper stories, I say, are required to be accurate, not even-handed. Surely you are asking something of newspapers that they were never set up to deliver?

"They are perfectly at liberty to do that [not being even-handed] but if they're going to do that then they should expect that we will highlight that." Would he be sad if the Daily Mail closed? "No." How about The Scotsman? "No."

Like Guido Fawkes and the US-based Drudge report, Wings is an internet phenomenon: on top of 4.5 million page views, 250,000 unique users visit the site every month. Campbell works around 14 hours a day on the site and is the poster boy for a certain type of online independence campaigner.

And yet, Yes Scotland - the official campaign group for independence -won't touch Wings with a barge pole. Yes recently ordered a local group to stop distributing leaflets that endorsed the website.

A senior Yes figure told the Sunday Herald that the reason for this distance can be summed up in one word: Hillsborough.

In September 2012, an independent panel confirmed that policing failures, not Liverpool fans, were to blame for a crush that led to the deaths of 96 people.

But on the day after the panel issued its findings, Campbell wrote a piece that pointed the finger squarely at Liverpool fans: "The police's mendacious attempts to blame the fans for being drunk, late or ticketless were red herrings. The reality is much simpler, and required no lying - the fans were to blame because they, alone, were the ones who pushed and thereby caused the crush."

Campbell now says of the article: "Some people are upset at some of my personal views. I struggle to see what conceivable relevance they [his views] are. I stand absolutely by the stuff that I've written about Hillsborough."

But the panel said a lack of police control was to blame, not Liverpool fans.

"The inquiry has a very specific definition of blame. Listen, this isn't something that I particularly want to get into here. As I say, it's nothing to do with Scottish politics."

It's the reason people in Yes won't deal with him: "The bottom line is I don't particularly care if people don't want to be associated with us."

Does he regret publishing it? "No. As far as I am concerned, it is true." However, it would be wrong to say that Yes Scotland has had absolutely no contact with Campbell.

Asked whether he had ever spoken to Yes chief executive Blair Jenkins, Campbell said: "I have spoken to Blair on a number of occasions."

When was the last time? "I'm not particularly sure I want to reveal that."

Wings has also attracted money, with fundraisers reeling in nearly £150,000 from supporters.

As a result, Wings registered as a referendum campaigner, which means the source of donations over £7500 has to be declared.

The website received a £10,000 donation from a supporter, but this has not shown up on the register. He says the £10,000 will be spent after the referendum, which falls outwith the rules.

So who is the donor?

"It was somebody who did appear on the Electoral Commission's list of donors that was published the other week," he says. Campbell declines to name the donor, but he rules out tycoon Brian Souter and lottery winners Colin and Chris Weir.

Looking ahead to September 18, the Wings founder says he has "no idea" what the result will be.

However, he worries about the effect of a No vote: "The psychological damage to Scotland as a whole will be enormous."

One remaining mystery is Campbell's use of the word "Rev" before his name.

He does not have a university qualification, but he says he became a reverend in the 1990s.

Does he do weddings? "I have not done weddings."

Funerals? "No."

Does he believe in God? "Things evolve."

He says he uses Rev because a stalker used to edit his Wikipedia page in a way that directed people to a different Stuart Campbell who was a murderer.

Campbell is an IT-literate troublemaker who has a long history of winding people up. A combination of the referendum, the internet and an edgy electorate has given him the perfect canvas.