Nice guys finish last, so the saying goes. There is one man, though, whose recent chart success seems to challenge that maxim. Official figures show that Ed Sheeran, who has persisted with his scruffy image and simple songwriting, was the biggest-selling artist of 2014 with his second album, X. He is Britain’s biggest export since Downton Abbey.

Sheeran, already the most searched-for male celebrity on Google, may well see his career scale further heights in 2015, with two Grammy nominations and three nights at Wembley Stadium in July – two of which are sold out. Performing with only a backing band, loop pedal and an acoustic guitar, he is about to pull off the biggest busk of all time.

So how did Sheeran, a relatively normal bloke, making relatively normal music, manage to become Britain’s biggest-selling artist?

Niceness alone, of course, doesn’t account for his blockbuster success with album X; it sold 1.7m copies in 2014 in Britain, one of only two releases to beat the 1m mark, and has had over 430m streams worldwide since its release in June – more than any other artist globally. Perhaps it is more thanks to Sheeran’s skills in balancing his guise as the bastion of shabby student authenticity with the role of mercurial businessman – not to mention a fierce sense of underdog ambition.

Facebook Twitter Pinterest Ed Sheeran poses with singers Taylor Swift and Ariana Grande and Victoria’s Secret models at a London fashion show in December. Photograph: Karwai Tang/WireImage

A bit of luck helps, too. The initial spark for Sheeran’s stratospheric success can be traced back to two chance events. The first occurred during an impromptu LA trip in 2010, which led to a friendship with the actor and musician Jamie Foxx. Foxx saw Sheeran play and ended up providing him with exposure in the US on his radio show, The Foxxhole. That same year, Sheeran’s music was noticed by the web mogul Jamal Edwards, whose online channel SB.TV has shone a light on the wealth of talent emerging from the UK grime scene. The SB.TV connections led to Sheeran collaborating with established grime artists including Wiley, JME and Sway, while he simultaneously worked the grind of indie venues in London, performing 300 shows in 2010 alone.

With opportunities opening in both the US and UK, Sheeran was able to establish fans on both sides of the Atlantic – an accomplishment many musicians are unable to crack throughout the duration of their career.

George Ergatoudis, head of music for Radio 1 and 1Xtra, believes Sheeran’s ability to straddle a multitude of modern genres makes him stand out. “He switches between folk music and black music in a unique way … no one else channels Eminem and Damien Rice simultaneously like he can,” he says.

Such careful cultural curation appeals to a range of ages, genres and genders, and allows Sheeran to be playlisted on Radio 1, Radio 2 and BBC 1Xtra. The latter channel named him the most powerful artist on its annual Power List – a choice that triggered controversy, given 1Xtra’s description as the “black music network”.

As well as catering for the indie crowd and pop audiences – the singer has toured with Taylor Swift – Sheeran’s honeyed vocals and dalliance with rap styles has also helped increase his trajectory in the US, where hip hop and R&B is a far more lucrative business than in Britain. This year he collaborated with rapper The Game and appeared on the cover of the influential rap magazine Vibe.

Facebook Twitter Pinterest Ed Sheeran - You Need Me, I Don’t Need You

Although much rap music can be about bragging, intrinsic to Sheeran’s aesthetic is his ability to appear everyday. Material on his debut album, +, had an obsession with promoting his allegiance to reality (“Selling CDs from my rucksack aiming for the majors/Nationwide tour with Just Jack/Still had to get the bus back”), and his Twitter feed is a constant source of disarming truths, such as “doing the Victoria secrets fashion show tonight and I’m eating a Greggs sausage roll in the dressing room”.

Ed Sheeran (@edsheeran) Doing the Victoria secrets fashion show tonight and I'm eating a Greggs sausage roll in the dressing room

Eric Clarke, professor of music at Oxford University, thinks this is a potent attribute for an artist in 2014. “His boy-next-door [image] – not very good looks but a perfectly nice guy – and the song Thinking Out Loud, with its reflections on getting older and fidelity and love in a fairly conventional context, is a slight counter-blast to fast-living celebrity culture.”

This sense of self-imposed legitimacy also taps into the kind of heartfelt testimonies found on X Factor.

According to the book Faking It: The Quest for Authenticity in Popular Music, there are three kinds of authenticity in music’s history: cultural authenticity (appearing true to your culture), personal authenticity (appearing true to yourself), and representational authenticity (not “faking it” in terms of how you record your music).

Hugh Barker, the book’s co-author, says that cultural authenticity has become slightly less important over time as music is increasingly globalised. He says: “Personal authenticity seems to be more prized than ever. Before the late 60s, there were very few songs that directly referenced the writer’s life. That changed with songs by people like John Lennon, James Taylor, Carole King – and since that time autobiography has become ubiquitous, and is often used as a badge of authenticity.”

Facebook Twitter Pinterest Ed Sheeran – Thinking Out Loud

A far more straightforward explanation for Sheeran’s global impact lies within his songs. Fiona Bevan, the singer-songwriter who co-wrote One Direction’s Little Things with Sheeran, pins the copyable nature of his songs on the youth market’s current captivation with him.

She says: “Because of the fact that Ed plays solo guitar, and you can hear the acoustic guitar part on the records, the songs are accessible to people to learn to play at home. All his songs are so well written that you can strip away all the production and the songs still stand in their own right. I think the YouTube generation gravitate towards this clear, seemingly simple songwriting when they want to cover their favourite songs, and share them with their networks – so there’s this incredible surge in awareness from fans on YouTube making their own versions and spreading them far and wide.”

To others, Sheeran’s ascent is baffling, perhaps even offensive to those who hoped that the voice of a new generation might be more revolutionary. In 2012, the influential journalist Caitlin Moran tweeted: “If my kids ever tell me they like Ed Sheeran, I’ll put them in a sack and throw them in a canal.” Sheeran’s response was to sidestep a potential social media spat by sending her “lots of hugs” via Twitter, prompting regret and a grovelling offer of drinks on the part of Moran. Which just goes to show that you never should underestimate the potency of being nice.

Artist album chart 2014

1 Ed Sheeran X

2 Sam Smith In the Lonely Hour

3 George Ezra Wanted on Voyage

4 Paolo Nutini Caustic Love

5 Coldplay Ghost Stories

6 Paloma Faith A Perfect Contradiction

7 One Direction Four

8 Olly Murs Never Been Better

9 Pink Floyd The Endless River

10 Take That III

Most streamed artists 2014

1 Ed Sheeran

2 Sam Smith

3 Arctic Monkeys

4 Eminem

5 Calvin Harris

6 Coldplay

7 One Direction

8 Beyoncé

9 Katy Perry

10 Bastille

• This article was amended on 1 January 2015. It mistakenly attributed a quote about Sheeran’s boy-next-door image to Keith Negus, professor of musicology at Goldsmiths, University of London. In fact, it was a professor of music at Oxford University, Eric Clarke, who was interviewed and quoted. This has been corrected.

