That was back in the day when the sun never set on the British Empire, as they liked to say.
After breaking the long drought — with a very British "hat trick" on Saturday night — the fans were singing "Rule, Britannia." Others were belting out "God Save The Queen." David Bowie's song "Heroes" was replayed, and replayed, and replayed.
Ennis' win in the 800 metres, the last of her seven events in the heptathlon on Saturday night, was like a coronation. She took two victory laps of the main, 80,000-seat stadium in London.
Cue raucous, almost deafening cheers. Red-white-and-blue Union flags waving everywhere.
Greg Rutherford chimed in with an unexpected victory in the long jump about 20 minutes later — ideally for the British, he beat Mitchell Watt from the upstart former colonies in Australia — and Somali-born Mo Farah won the 10,000 metres inside the hour.
Jolly good show, Britain.
Ennis kicked it all off in the very first event on the track on Friday, winning the 100-meter hurdles in the fastest time ever in a heptathlon. She was under enormous pressure, considered Britain's best shot at a track and field gold medal in London. She never wilted in seven disciplines across 36 hours.
"I'm just still in shock," said Ennis, the daughter of Jamaican and English parents who grew up in the industrial city of Sheffield. "It's been a brilliant couple of days.
"You know, I've come into this competition with a lot of pressure. Everyone expected me to win the gold medal before I'd even stepped on the track, so to have come here in one piece and to have delivered and completed the whole heptathlon and won was just a dream come true really."
The 26-year-old Ennis missed the 2008 Olympics due to injury, won the world title in 2009 but surrendered it last year in South Korea.
"I just can't believe I've done it," she said. "All that pressure is off me now. It's so nice."
Some of Farah's family ran into the arena to celebrate with him when he won the last final of the night, showing no reservations or restraint. And nobody intervened. In fact, fans, friends, people he'd never met were queuing to congratulate him.
"It's just amazing. If it wasn't for the crowd I don't think that would happen," Farah said. "They give you that lift, that boost. It's just incredible.
"A lot of people thought having the Olympics in London was a lot of pressure (but) you've just got to use the crowd. I think every single one of us who won a gold medal used the crowd."
The roars around the stadium have been compared with a jet airplanes taking off, definitely a boost for Team GB. Then there's people who don't have tickets but have flooded into London.
"The crowd were amazing. I'm worried I'm going to wake up from it," Rutherford said, reflecting on his long jump competition. "As I ran down the runway, they got louder and louder."
After they'd done their laps with the Union flag — Ennis had one pre-printed with "Jessica Ennis, London 2012, Olympic Champion!" — all the British winners were ushered into news conferences underneath the stadium. A team press attache probably didn't even mean to boast when he said: "I've got a queue of Olympic champions."
Most Olympics have major moments. Britain's Jonathan Edwards, an Olympic triple jump champion in 2000, recalled the "Magic Monday" at Sydney a dozen years ago, when Australia's Cathy Freeman was among a host of great athletes who won gold on the same evening.
Ennis inspired Britain's "Super Saturday."
Despite losing in a penalty shootout in the men's soccer tournament, Britain also won cycling gold in the women's team pursuit and won two rowing gold medals in the men's four and women's lightweight double sculls. Andy Murray can add another in the tennis final at Wimbledon on Sunday.
But even that will struggle to compare with what happened Saturday.
"That won't be topped," Edwards said as the crowd filed out of the Olympic Stadium. "To see a night like that — Jess Ennis set up to be the 'Golden Girl,' Mo the 'Golden Guy,' Greg Rutherford to come from almost nowhere to win a gold medal. It's just staggering. You need a new lexicon, actually. You run out of words to describe that."
London Mayor Boris Johnson, never lost for words, was among the proudest of supporters.
"Team GB's glutinous desire for gold shows no sign of being sated," Johnson said. "Their extraordinary efforts have brought rapture to streets, parks and living rooms in London and all over the country, if not the planet."