Jenson Button completed one of the most remarkable comebacks in the history of sport last night by becoming Formula One world champion after a thrilling Brazilian Grand Prix. It was the first time since 1969 that the championship has been won in consecutive years by British drivers, with Button succeeding Lewis Hamilton, who also won his title in tense circumstances in Brazil a year ago.

But unlike Hamilton, who was the product of McLaren Mercedes, one of the sport’s wealthiest teams, Button was lucky to be on the grid at all.

Just 11 months ago Button, 29, was out of a job and facing the prospect of never driving in Formula One again after Honda quit the sport, victims of the financial global crisis. He had turned down four teams to pledge his loyalty to Honda with a new three-year, £24 million contract, only to discover the Japanese carmaker was walking out of Formula One for good.

The team was rescued by Ross Brawn, its Manchester-born team principal, who put his own name over the door and asked Button to stay to lead the revival. To make sure the new Brawn GP team could balance its books, Button even volunteered to take a £5 million-a-year salary cut and to pay his own expenses to the 17 grands prix around the world.

The sacrifice was worth it as, against all expectations, Brawn produced a spectacularly fast car and Button won six of the first seven races. He has led the world championship from the first race of the season and yesterday only had to keep Rubens Barrichello, his team-mate, in his sights to make sure of the championship with one race still to run in a fortnight in Abu Dhabi.

The fairy story, though, looked as though it would be written by the Brazilian in front of his ecstatic home fans as he took an astonishing pole position on Saturday in desperately wet conditions after rainstorms swept through São Paulo. But Button, who started in 14th, drove courageously, pulling off a series of breathtaking overtaking manoeuvres to take sixth, while Barrichello suffered a puncture.

He finished a disconsolate eighth, leaving Button to take the title.

A joyous Button had screamed his celebrations into his helmet on his final lap of the dramatic Interlagos track, even singing Queen’s ubiquitous anthem, We Are the Champions, over his car radio in a croaky baritone to his bemused mechanics.

In the paddock afterwards, Button said: “It is unbelievable. I first jumped into a kart 21 years ago and I never thought for one second that I would be the Formula One world champion. After my career of ups and down, this is just fantastic.”

The biggest hug was reserved for John Button, his tearful father, who has watched every race of his son’s career since buying him a go-kart for his eighth birthday. As he realised just how talented his son was, John travelled across Britain with him, sometimes even having to borrow petrol money to get home.

Button had promised to be one of the best drivers of his generation as a teenager and soon attracted the attention of Formula One. Sir Frank Williams, one of Formula One’s greatest team owners, telephoned Button in a pub to offer him a test drive. Button thought it was a joke but a month later, he was a fully fledged Formula One driver at the age of just 19.

Though he became Formula One’s youngest points scorer in only his second race, also in Brazil, it took him 113 attempts to win his first race in 2006. Last night, however, Button’s determination to succeed against the odds won through as he was crowned Formula One world champion.

Life in the fast lane

• Born on January 19, 1980. Home was in the tiny village of Upper Vobster, Somerset

• Failed driving test after five lessons at the age of 17, but passed after six

• Estimated to be worth £30 million

• Lives in an apartment in Monaco.

• Drives a Smart car or a Vespa

• Celebrity girlfriends have included Louise Griffiths, Florence “Flee” Brudenell-Bruce and Jessica Michibata, a swimwear model