Like Jake and Elwood, Jack White felt he was on a mission from God to bring the blues screaming into the present day. Though his purpose was almost derailed when the teenage guitarist confused the spiritual feelings he registered from this genre with the call from the man upstairs to be ordained. The mix-up arose from the fact that "blues singers have the same feelings and emotions that someone who is called to be a priest might have," White later said. The Detroit-born Roman Catholic and youngest son of 10 children might have ducked the priesthood, but he’s been edging ever closer to the Vatican in the psychogeographical sense ever since.

The fact he appeared on the Ennio Morricone-inspired Danger Mouse album Rome in 2011 is probably neither here nor there - some associations run deeper. The title he chose for his second solo album - Lazaretto - comes from a series of centralised fortresses that were run by clergy and set up to manage the plague in Italy and across Europe during the 16th century; the name of course is a reference to Lazarus, the man brought back from the dead by Jesus in the Gospel of John. Given the slim chances of overcoming the zoonotic disease once it was contracted (an affliction from God for the wages of sin according to the friars), one can only assume the nomenclature was ironic.

In 2006, when Italy won the World Cup in Germany, another resurrection of the unlikeliest kind appeared to be taking place, when the Azzurri crowd could clearly be heard chanting the riff to The White Stripes' most famous hit. ‘Seven Nation Army’ (the title, incidentally, came from the infant White getting the Salvation Army’s name wrong) had reached No 76 on the Billboard Hot 100 three years earlier, a respectable chart position for an alternative rock song. In the UK it went as high as No 7 but scored its highest position in Italy, where it peaked at No 3. XL had run a successful PR campaign in support of the lead single from Jack and Meg's then-new album Elephant, but nobody predicted the spectacular afterlife that was to come.

'Seven Nation Army' became synonymous with the Italian homegrown heroes of the World Cup: Cannavaro, Totti, Gattuso, Nesta and the rest, and Alessandro Del Piero and Marco Materazzi even joined The Rolling Stones on stage for a rendition when the veteran rockers played in Milan shortly after the final. It began to seep into the culture too, with indigenous dance/hip-hop acts like Two Fingerz and Caparezza just two examples of artists who sampled or replayed the riff in their own work towards the end of the decade. This wasn’t just happening in Italy either; in 2009, a wedding band called Black Cats, based in Ahmadinejad's Iran, took White’s riff and used it in their song 'Boro'. I found it impossible to contact Black Cats despite some concerted effort, though the riff itself had no such bother, breaching the borders of Iran and making itself heard and available.

It was easier to speak to Ben L’Oncle Soul, an R&B singer from Chambray-lès-Tours, France, who recorded his own version of the song. I asked him what it was about 'Seven Nation Army' that appealed to him enough to cover it.

"Inspirational," was one superlative he used. “The riff and the lyrics touched me, because it's a hymn to freedom, and the world wants to be free." Speaking of free, Marcus Collins, an X Factor runner-up in 2008, also recorded his own version of the track that suspiciously seemed to take Ben L’Oncle Soul’s arrangement and copy it moment for moment. “I never heard that version,” Ben says, magnanimously. It's curious that Soul's version (and so Collins' version) actually omits the riff, given that he'd been listening to a lot of reggae and Stevie Wonder at the time.

Among the rash of other covers and adaptations, even Miami house numbnuts Pitbull got in on the act with 2010’s ‘Gimme A Bottle’, though it’s sport where the real appeal of that guitar line seems to lie, and its ubiquity since its inception some 13 years ago is nothing short of phenomenal. The seven-note sequence has been heard reverberating around crowds at every World Cup since 2006; it gets sung everywhere from the World Series and the Super Bowl to lawn bowls; it's like the aural equivalent of a Mexican Wave, transcending a single sport and appearing out of nowhere when enough spectators are gathered together, regardless of the event. It’s an international craze that infests all areas of sporting life, sung by fans home and away. It is a genetically durable automaton that other weaker chants can only look upon in envy. It is strong, adaptable, easy to unpack and possibly unkillable. At Christmas I witnessed my brother chanting the name of the Dutchman Michael Van Gerwen to the tune of the song while he drank lager and watched darts on TV. In the summer I heard robust youth roaring it as they beat a volleyball to each other on the Cote d'Azur while I lay back on the beach like a nymph from Luxe, calme et volupté - that was the moment I started thinking about this article. In more serious news, it cropped up during the Arab Spring, with journalist Mona Eltahawy describing how it went through her head as the people of Egypt sought to overthrow Hosni Mubarak.

If we're all quite aware of what it has become, then where did it come from? From Jack White’s guitar of course, and from his fingers and his brain. But what about the sequence of notes? Could they have been hanging around in the universe since the cosmic microwave background splurged into existence, just waiting to be aligned by a malleable composer? Speaking to the BBC last year, Tom Morello of Rage Against The Machine said: "It's less a riff that feels like someone wrote it than it was unearthed. It's something that's always been there, and it's something that speaks to the reptilian brain of rock listeners."

Chilly Gonzales, a man whose forthcoming Chambers album does what it says on the tin, and who recently published the Re-introduction Etudes book for lapsed pianists, knows a thing or two about musical theory. And he’s not so sure.

“I've said this here and there when I've come up with something that just seemed like it already should have existed. It also happens to be a romantic idea, but to me it smacks of false humility and wishful thinking. Most of the time, it's because it is very similar to something that exists, but no one catches it.

“Certain rhythmic approaches, instrumentations, and the passage of time and the distance between genres make it possible for the subconscious semi-plagiarism to go unnoticed. And Morello's rationalisation removes the less romantic possibility that [Jack White] unwittingly ripped something off and got away with it.”

Intriguingly the Seven Nation riff has been around longer than one might have realised, first making an appearance out of fin-de-siecle Vienna when the refrain appeared fully formed in Anton Bruckner’s Fifth Symphony, although listening to the piece, it’s hard to imagine that’s where White got it from. The disparity in the musical visions and the completely different contextualisation of the phrase makes one imagine that were Bruckner alive now (and he’d be 190 if he was), he’d unlikely be troubling the metro-Detroiter with any kind of lawsuit. Closer in spirit to the White Stripes hit is 1985’s ‘Mighty And Superior’ by hardcore band Conflict, which uses almost the same configuration of notes - but it hurtles along without Meg White’s syncopated bass drum groove, which should certainly not be a forgotten ingredient in the recipe of this riff’s rise to infamy.

"It is an epic riff, certainly, but don't underestimate the White Stripes' performance and attention to detail," says Jim Watts, who played guitar in the incarnation of The Fall that recorded 'Theme From Sparta FC'. "Meg White's drums are very dry and unprocessed. Jack White's guitar and vocals just drip excitement. I have never heard a cover of that song that was anywhere near as good as The White Stripes' version."

Also, it should be noted that while the song first came largely to the world’s attention at the Olympiastadion in Berlin - the scene of Italian triumph and an ill-advised headbutt by a Frenchman - there’s actually a Belgian connection to this story that goes as far back as 2003, when Club Brugge were in Italy for a Uefa Champions League tie against AC Milan. Travelling fans heard the track on the radio while sat in a cafe ahead of the match, and according to Deadspin.com, took the "Ohh oh-oh-oh oh ohh ohh" into the San Siro with them. The visitors took an unlikely lead away from home through Peruvian forward Andrés Mendoza, and as the tension mounted, the song got louder and louder until the final whistle when the unfancied team took home the three points. For those delirious fans, just singing the same constellation of notes in the future would trigger feelings of euphoria all over again. The chant followed them back to Bruges, where they spread it like a virus around the Belgian Pro League. Whether Italian fans started singing it around this time or later is unclear. What is clear is that those Club Brugge supporters could have had no idea what they were unleashing unto the world.

So what is it that makes a good chant? There needs to be "a simplicity to it", according to Sheffield Wednesday fan, Sheffield Star columnist and influential football blogger Laura Jones. "It has seven notes with a very deep bass. It has quite a tribal beat which lends itself to sport."

Nothing too challenging then?

"Complex songs start to limit the amount of people who might join in," she says. "The whole idea of a chant is that it brings the collective together to get behind their team. It's a bonding tool."

"I think it has caught on because it's such a simple riff," concurs Oldham Athletic fan Peter Headen, "and because it sounds a bit menacing. It has the air of a war chant about it."

Peter says it was more prevalent at Boundary Park when the team had the striker Jonson Clarke-Harris, because his name so perfectly fitted the notes syllabically, though it has died off somewhat since they sold him to Rotherham and didn’t replace him with a player with a five or seven syllable name. Do Sheffield Wednesday fans sing their chant to a favourite forward?

"It's not sung to a particular player," says Laura Jones. "Sheffield Wednesday fans sing 'dirty red and white bastard' which is in reference to Sheffield United. It's also sung at anyone in a red and white strip who makes a dirty challenge."

"Despite the ridiculousness of the idea that 50 Oldham fans singing someone's name to the tune of a White Stripes song away at Gillingham would be in any way intimidating," says Headen, "Make that 50,000 at the Bernabeu or at a World Cup, and it may be a bit more stirring. I think that's probably why it caught on."

"It's repetitive and inclusive," adds Jones, "even if you are using it to swear at another team."

So we’ve established what makes a good chant, but what makes a good riff? Is there an art to it? Presumably it's elusive or hit records would be guaranteed…

“Exactly,” says Gonzales. “A bit like when a musician friend might proffer that it's easy to write a hit song. The obvious rejoinder: then go do it!”

Frankie Poullain of The Darkness helped usher in one of the most recognisable riffs of 2003, the year ‘Seven Nation Army’ was also in the charts. In fact ‘I Believe In A Thing Called Love’ was only held off the No 1 spot by ‘Where Is The Love?’ by The Black Eyed Peas, which still makes painful reading 12 years on. Poullain must have a theory regarding this.

“A riff on its own isn't worth shit, if it was then Joe Satriani would be bigger than Elvis. The gold dust is the juxtaposition of a riff's repetition with the melodic poetry of a human voice. Riffs can't be approached mathematically like a computer, there's normally something 'wrong' about a great riff, some illogical step in the progression that somehow resonates.

“If you approach them self-consciously, they come out rubbish - like most things in life. There's definitely an art to them.”

Jim Watts says there’s no real formula either: “Some of the greatest riffs are just three notes or less. The rhythm they are played at is far more important. Which way they go is just for flavour. Great riffs are just too cool to care about music theory.”

Is "which way they go" important? For instance, are human brains more receptive to a descending scale - used so often by the Beatles - than they are to an ascending scale? 'Seven Nation Army' probably belongs more in the former category.

"You might have a point there," says Poullain. "Tolstoy said, 'All happy families are alike; each unhappy family is unhappy in its own way.' Ascending scales depict an optimism which is clearly unrealistic given what human nature is really like. People feel foolish and chastised when their optimism is cruelly deflated by reality - ergo the dark side and descending scales are a safer bet, and there's the added bonus, as Tolstoy inferred, of being a truly original miserable bastard."

"I don't think so," says Chilly Gonzales. Here he takes us through the theory. You may want to hold onto something.

"It actually involves an initial rise of a minor third before descending," he points out, pedantically. "My guess is that great hooks require a mix of surprise and satisfaction. 'Seven Nation Army' is more of a veiled chord progression than a melody. It begins on the one, up to a brighter three, down to a tense six, then lowered to a five. A five begs to be resolved to its home destination, the one. So there is a neutral establishing note, and a brief trip through bright, tense and the most common resolution of all, five-one. There might be something to the fact that the second iteration of the theme adds a small variation that accomplishes some kind of storytelling with minimal means."

Right, we’ve got all that. And how about the rhythm?

"There is a very distinct use of triplets," he states. "The third, fourth and fifth notes of the riff are staggered in a way that might suggest drunkenness, or again, a meathead sensibility. This is the moment that might invite the deployment of devil horns with the 2nd and 4th fingers. It's almost medieval."

"It's raw rather than simple," says Jim Watts. "Simultaneously stupid and sophisticated."

"It's very human in that it's played on a guitar and it's raw and primitive," adds Frankie Poullain. "It's also a blues song. This helps it to connect in a way that a mechanical synth or digital sound is unable to.

"I suppose there's the comfort and reassurance of hearing something short and self-contained and the security of knowing it's going to land in exactly the same way every single time. It's partly about wanting to be a baby again. Or a moron. Same thing really."

And what about Jack White's take on it? The White Stripes man and progenitor of the 21st century’s most famous guitar riff surely deserves the final word.

"I am honoured that the Italians have adopted this song as their own," he said, when asked about it shortly after the World Cup in 2006. "Nothing is more beautiful than when people embrace a melody and allow it to enter the pantheon of folk music. As a songwriter it is something impossible to plan, especially in modern times. I love that most people who are chanting it have no idea where it came from."