Four years ago New Orleans was a broken city, its streets and houses submerged under 40 billion gallons of stinking water, its people destitute, homeless and scattered across the nation, its very future called into question by the apocalyptic destruction wreaked by Hurricane Katrina.

Having plumbed the depths of despair, the Big Easy was yesterday engulfed by joy and euphoria after the Saints — its beloved but perennially woeful football team — won Sunday night’s Super Bowl for the first time in its 43-year history.

It was a victory that transcended mere sport. It was a victory for an underdog team that triumphed over adversity; for a singular bunch of players who have done so much — on and off the field — to rally New Orleans; and for a city so inspired by their example that it simply refused to die.

“We knew we had an entire city, maybe an entire country behind us. We’re feeling it was all meant to be. It was destiny,” said Drew Brees, the star quarterback. The tears rolled down his cheeks as he spoke, roared on by 75,000 fans in the Sun Life stadium, Miami — and many millions of others across America.

Tracy Porter, the Saints cornerback and a Louisiana native, said: “Words can’t describe how much this means to New Orleans.” It was his interception and 74-yard sprint that sealed his team’s victory.

“New Orleans is back and this showed the whole world,” said Tom Benson, the team’s owner, as he danced a jig on the winners’ podium.

Back in New Orleans, in Bourbon Street, Jackson Square and the French Quarter, in neighbourhoods that were until recently scenes of dereliction, the city erupted in one giant party that lasted till dawn and set the scene for the ultimate Mardi Gras celebrations over the coming week.

People poured on to the streets in the team’s black and gold colours, dancing, hugging and weeping. “Who dat? Who dat? Who dat say dey gonna beat dem Saints?” they chanted. Jazz bands let rip. Bars blasted out When the Saints Go Marching in. Fireworks exploded.

Police officers gave up the pretence of staying aloof and joined the pulsating throngs. Strippers stopped dancing. Priests and nuns joined the uproar. The city’s newspaper, The Times-Picayune, printed nearly 200,000 extra copies of an edition that is certain to become a collector’s item. Even dogs were dressed in Saints shirts, and Mitch Landrieu’s election on Saturday as New Orleans’ first white mayor in three decades was overshadowed.

“It was the best night of my life,” said Charlene McBride, 57, a hotel worker who had lost her home in Katrina and stumbled into work at 6.30am after partying till the small hours. “We will remember Katrina but the Saints winning makes us look to the future and forget the past.”

“This is the pinnacle of my life — now I can die,” exclaimed Randy Smith, who left New Orleans after Katrina but returned to watch the game with his old neighbours.

“The Saints are not the same as other sports teams. They represent the rebirth of the city,” said Lisha Barre, one of thousands of outsiders who flew in to watch the game. New Orleans had waited a long time for this moment. The team, which was founded in 1967, went two decades before it won more games than it lost in a season. The Saints were so dire that they were dubbed the “Aints” and fans wore bags over their heads for shame.

And then came Katrina. A city barely large enough to support a top-flight football team lost between a third and a half of its population. The Superdome was trashed first by the hurricane, and then by the 30,000 homeless people who took refuge in its dark and sodden interior. The Saints moved to Texas and might well have stayed there had the fans not raised such an outcry.

A thousand labourers restored the Superdome in one year flat. Brees, a devout Christian, and other stars joined the Saints precisely so that they could help to rebuild the city. The fans, though depleted, bought all 70,000 season tickets for the first time ever and the Saints, in their first season back, reciprocated by reaching the play-offs and bringing hope to a city where there was none.

They were just as inspiring off the field, visiting schools and hospitals, rebuilding homes, using their celebrity to raise millions of dollars and giving freely of their time and money. Brees alone raised more than $3 million (£2 million).

New Orleans always loved the Saints, however bad they were, but in four years that love has turned into an all-consuming passion that reached its apogee on Sunday night.

“Four years ago whoever thought this would be happening?” asked Brees, whose future had looked as dark as his adopted city’s in 2005 because of a serious shoulder injury.

“When 85 per cent of New Orleans was under water, all of its residents evacuated to places all over the country, most people were wondering if New Orleans would ever come back or if the team would ever come back.

“It’s unbelievable. I don’t think it’s sunk in yet. Just to think of the road we’ve travelled and how much we’ve invested, how much adversity we faced along the way, how many people believed in us and gave us the strength to go out and do what we did tonight.”

An estimated 106.5 million Americans saw the game on television, making the Super Bowl the most watched programme ever. The Saints, with their stirring story, have undoubtedly usurped the Dallas Cowboys as America’s favourite team.

Tens of thousands — perhaps hundreds of thousands — of fans greeted the players on their arrival last night at New Orleans airport and as they made their way into the city. Today the team will have a victory parade that, for sheer jubilation and exuberance, is likely to eclipse even the greatest of this illustrious old city’s Mardi Gras extravaganzas.

A broken city

— Hurricane Katrina hit the US Gulf Coast with winds of up to 130mph (210km/h) on August 29, 2005, killing more than 1,800 people, driving 2.16 million from their homes and causing $75 billion (£48 billion) of damage

— About 80 per cent of New Orleans was under water, with the flood depths reaching 20ft (6m)

— The Government budgeted $200 billion on reconstruction, ordinary Americans donated $587 million and other countries sent donations

— The Bush Administration was accused of being slow and inefficient in responding to the first major disaster since September 11, 2001. Notably, the evacuation the day before the hurricane made no provision for the poor, elderly and sick. By 2008 the city had still received only half of the federal funds allocated to it

— Of 455,000 inhabitants before the hurricane about 76 per cent have now returned to their homes

— The city’s homeless rate reached 1 in 25 in 2008, although it has since fallen

— Most neighbourhoods have been rebuilt but some remain uninhabitable. The Lower Ninth Ward, once home to 14,000 people, still has no street lights, supermarket or high school

— In December Barack Obama said that he had released $1.4 billion of aid that had been tied up in red tape and promised not to repeat the mistakes of the Bush Administration

— Houses in many poor areas still have a 26 per cent chance of flooding in the next 30 years

Sources: Brookings Institution, Reuters, National Academy of Sciences