To understand how Burnley are on the brink of Manchester United, Arsenal and Chelsea, you have to understand Leyton Orient. They were the opponents for the most significant match in Burnley’s recent history, and to Burnley, history matters. More than most clubs, who Burnley are is who they were. Their intimate relationship with the past is one reason why it would be a sweet shock to see them in the Barclays Premier League next season.

They are a victory from the competition that thinks of 1992, its first season, as football’s Year Zero; the league of constant, restless expansion, of money, more and more; of the modern, the exotic, the glamorous and the global. Unlike Sheffield United, their opponents in today’s Coca-Cola Championship play-off final, Burnley do not own a team in the Chinese Super League. They think more about Accrington than Asia, they fret about Blackburn rather than dream of exploiting Beijing. They are still local, still little and still connected to their community, still embracing the sort of working-class credentials that other clubs try to suppress.

The town is hugged by Pennine hills, sheltered from the wider world. There is still a Burnley Miners Social Club, a short walk from the ground, though the last pit shut in the early Eighties. It all sounds like a recipe for insularity, but it has bred solidarity. Turf Moor lies at Burnley’s heart, in every way. The club are taking their full allocation of 36,000 fans to Wembley today, although the town’s population is only about 88,000. Last week, cars in the town centre proudly flew claret-and-blue flags, posters were up in shop windows and souvenir stalls did a brisk trade.

With a pair of first division titles (1921 and 1960), one FA Cup (twice runners-up) and two European campaigns, Burnley’s pedigree means that their rise to the Premier League would not feel artificial, as Wigan Athletic’s does. Burnley do not have a sugar daddy or a sheikh.

Burnley won the first division title in 1960 and they reached the FA Cup Final in 1962, losing to Tottenham Hotspur. When the maximum wage was abolished in 1961, bigger and richer clubs had an advantage, even more so when gate money became shared less equally. Burnley’s scouting system was pioneering but the pipe-line of young talent dried up when rivals developed their own networks. Burnley were relegated from the top flight in 1976 and have not been back.

By 1987, these founder members of the Football League had fallen so far that they faced being the first team automatically relegated to the Conference and financial collapse. A last-day win over Orient brought survival and the crowd of 17,000, six times the season’s norm, was a last-minute declaration of love that resuscitated a dying club. Since that turning point the story has been one of gradual progress, accelerating rapidly after Owen Coyle became manager in November 2007.

Coyle, a former Bolton Wanderers striker, was managing St Johnstone when Phil Gartside, the Bolton chairman, suggested him to Barry Kilby, the Burnley chairman. “He recommended this guy in Scotland,” Kilby said. “It was half-term and had I not been there on holiday I wouldn’t have spoken to him. He was very impressive.”

The 42-year-old was brought up in a tough part of Glasgow and his work ethic chimes with Burnley’s ethos. “I’ve said to my players that no one has ever handed me anything,” he said. “Everything you’re going to get, you’re going to have to go and earn and I think they know that – that’s why they work so hard.” Teetotal, Coyle would toast victory with “an Irn-Bru”.

Kilby, a local businessman, has been chairman since 1998. “We’ve always been grouped with the likes of Wolves and the Sheffield clubs, teams from big cities, but the reality is that Burnley is a smaller town than the likes of Rochdale and Oldham,” he said. “This club is the biggest thing Burnley has got. It helps the town punch above its weight.

“We would be the smallest club ever in the Premier League, in terms of the town’s population. We are already one of the smallest towns in the Football League. When we get 15,000 people in here, it’s the highest ratio of fans to population in the country.”

The club’s average attendance of 13,082 is the fourth-lowest in the Championship. Their wage bill is four times smaller than Birmingham City’s. Yet Reading were beaten in the play-offs with two spectacular goals at the Madejski Stadium that symbolised the attractive style of Coyle’s team. They like knockout football: this season brought a run to the Carling Cup semi-finals – Tottenham prevailed after extra time – with Chelsea and Arsenal conquered along the way.

“I’ve never known a time so exciting, so full of expectancy,” Jimmy McIlroy, arguably Burnley’s greatest player, said. He was an inside forward for the club between 1950 and 1963 and still lives in the town. A stand at Turf Moor is named in his honour.

“We played Tottenham Hotspur one dull, damp and dark November day,” he said. “I was standing at the entrance to the ground with my old pal Danny Blanchflower and fans walked past in cloth caps and mufflers and Danny said to me, ‘How the blazes do you live in a place like this?’ From the moment I arrived I felt at home. I was from a village in Northern Ireland. I’ve been almost hypnotised by this little town.”

As McIlroy’s reputation grew, clubs from Europe and South America wanted him. “A representative of an Italian club promised my children would be educated at an international school and we’d live in a villa overlooking the Mediterranean,” he said. “I told my wife, she thought for a moment and said, ‘What do we want to leave Burnley for?’ ”

Expectations of 1970s were castles in the sky

It was a prediction up there with “The British are coming” at the 1982 Academy Awards: Jimmy Adamson, one of their great players and Burnley manager between 1970 and 1976, claimed that Burnley would be “the team of the Seventies”. But they became a yo-yo club and have not been in the top flight since relegation in 1976, coming closer to going out of the Football League than reaching the Premier League. The changing landscape of British football made it harder for small-town clubs to compete at the highest level. But in the 1950s and 1960s the club were among the most successful in England, under the chairmanship of Bob Lord, an eccentric and controversial local butcher who developed the youth policy and, unusually, ensured the club had their own training ground. Under Lord, Burnley won the first division championship in 1960 and were runners-up in 1962, when they also reached the FA Cup Final. They made it to the quarter-finals of the European Cup in 1961.