Alex Cuthbert’s two second-half tries proved decisive in a match Wales had to win by seven points to retain the title for the first time since 1979, provided they maintained their superior try-count.
As it was the defending Grand Slam champions beat a 108-year-old record, surpassing the 25-point gap they achieved in their previous largest winning margin over England — 25-0 back in 1905.
“It’s unreal, it’s what dreams are all about,” said Wales flanker Justin Tipuric, who was named man of the match.
“We were outstanding, we all worked so hard, it’s brilliant. We knew what we could do, we talked about it all week and we were ready to play since Monday.”
Tipuric said Wales’s opening defeat at the hands of Ireland had inspired them to their victory.
“We got a lot of bad media. That gave us a kick up the backside, but we all stayed tight.”
England coach Stuart Lancaster admitted Wales had been the better side.
“We are gutted. We didn’t get the execution right and didn’t turn up,” he said.
“We just weren’t good enough. We have no complaints, we couldn’t match their physicality.”
After building a 12-3 lead early in the second half, through four penalties by full-back Leigh Halfpenny to one from England fly-half Owen Farrell, Wales surged ahead through a try by Cuthbert
That put them 17-3 in front and minutes later Farrell missed his second penalty in three attempts
Dan Biggar added a drop-goal before Cuthbert stormed in for another try, with fly-half Biggar completing the rout with a penalty.
This was Wales’s second victory in a row over England, with the Welsh the only side to defeat the English in Six Nations action since Lancaster became coach of the Red Rose brigade in 2012.
And the win also saw Wales end a run of five straight defeats at the Millennium Stadium in the most emphatic fashion possible, with the champions not conceding a try in the tournament since the 42nd minute of their opening defeat by Ireland.
Lancaster, who’d seen his side score just one try in their three previous matches, responded to a deeply unconvincing 18-11 win over Italy at Twickenham by making four changes.
He recalled half-backs Ben Youngs and the fit-again Farrell while up front prop Joe Marler returned and blindside flanker Tom Croft made his first Test start in 12 months following a career-threatening neck injury.
Interim Wales head coach Rob Howley lost one captain in Ryan Jones to injury and passed over another in Sam Warburton after the flanker indicated he wanted to remain in the ranks following last week’s man-of-the-match winning display against Scotland.
Instead fit-again loosehead prop Gethin Jenkins returned to captain Wales for only the fourth time in his 12-year career.
A frantic first half ended with Wales 9-3 in front, through three Halfpenny penalties to one by Farrell, whose first effort crossed after hitting the post, missing with his second attempt.
Early in the second period Wales, in a match played with the stadium’s retractable roof shut, laid siege to England’s line after centre Jamie Roberts was stopped by No 8 Tom Wood.
Their pressure led to a penalty which Halfpenny converted from wide on the left. Now, for the first time in the match, Wales had a title-winning lead at 12-3.
And they broke the game open in the 57th minute through Cuthbert’s first try.
Replacement hooker Ken Owens stripped Wood of the ball in the ruck and Wales worked possession to Cuthbert through scrum-half Mike Phillips and centre Jonathan Davies.
Cuthbert handed off England wing Mike Brown and completed a 40 metre move.
Halfpenny missed the conversion but Wales were in charge at 17-3.
Shortly afterwards Farrell, poleaxed by Wales No 8 Toby Faletau, missed the ensuing penalty before Biggar piled on the agony for England with a 65th minute drop-goal.
Wales then duly rubbed salt into England’s wounds with Cuthbert’s second try.
Warburton picked up the ball from the base of a ruck in his own half, brushing aside replacement scrum-half Danny Care and scything through the cover.
Tipuric carried on the move before drawing the cover to release the onrushing Cuthbert.
Biggar converted as Halfpenny received treatment before the fly-half added another penalty to seal the rout.