Wales ground out a 16-9 win over World Cup finalists France before an ecstatic capacity crowd at the Millennium Stadium on Saturday to complete a third Six Nations championship grand slam in eight seasons.
Flanker Dan Lydiate was named man-of-the-match thanks to a series of thunderous tackles on a treacherous surface which was soaked shortly before kick-off after France had asked for the roof to be kept open.
A typically ferocious Lydiate tackle on France captain Thierry Dusautoir midway through the first half forced a turnover which led to Alex Cuthbert scoring the only try of the match.
Cuthbert cut back inside from the right wing after the ball had been swiftly recycled for a converted try which gave Wales a seven-point advantage.
"It's a very young team and this was their first chance to win anything. To do it at home in the last match in the Six Nations, what could be better?," Lydiate said. "The crowd were our 16th man."
France, who defeated Wales by a point in their World Cup semi-final in New Zealand last year after Welsh captain Sam Warburton had been sent off, and Gethin Jenkins was pleased to turn the tables of France in Cardiff.
"We knew they were going to be good, they've played well all championship," he said. "The World Cup brought us tighter and losing to France spurred us on to get some revenge."
France relied on fly half Lionel Beauxis's kicking from hand in the first half.
They showed marginally more ambition after the break, reducing the deficit to four points seven minutes from time with a penalty from scrum-half Dimitri Yachvili.
Wales and their supporters were showing clear signs of nerves before fullback Leigh Halfpenny spun through a frantically back-pedalling French defence.
Replacement Francois Trinh-Duc, playing out of position on the wing, deliberately threw the ball away as he was forced into touch and Halfpenny converted a simple penalty with only two minutes remaining. Wales lost Warburton to a shoulder injury at half time but his replacement Ryan Jones proved at least as influential to demonstrate the strength in depth of the Welsh squad.
"It's something we will treasure for years to come," Jones, the former Wales captain, said. "For nine weeks the guys have been superb, I take my hat off to everyone, everyone has contributed."
Matthew Rees won his 50th cap against the French, having fought back from a calf injury to play his part in the campaign.
"I've worked so hard to get back," he said. "My second Grand Slam, 50th cap, I think I'll be doing some partying tonight.
"It was frustrating for me with the calf injury, for me it was just about getting myself back fit and being part of a successful team.
"We're still a young side, there's plenty still to achieve and we're looking forward to the World Cup in 2015."
Cuthbert added: "I thought we deserved it more than France. The feeling I'm feeling now I don't think I'll ever feel again."
England 30-9 Ireland
Italy 13-6 Scotland