England’s injury-hit team came from 10 points down to record a famous victory in Cardiff and take revenge for their record 30-3 mauling two years ago.
Maiden tries from Anthony Watson and Jonathan Joseph plus 11 points from the boot of George Ford hauled England back into a contest that had appeared lost and gave them the perfect start to their Six Nations campaign in what is a World Cup year.
Warren Gatland’s Wales – victorious in five of the last six games between the two at this stadium – had ridden a wave of noise and emotion to establish what looked like a critical early lead.
But 13 unanswered points in the second half from Stuart Lancaster’s inexperienced team silenced the fiery home crowd and set up arguably the finest win of the coach’s three-year tenure.
England had five players making their Six Nations debut and began the contest with 290 fewer caps than their hosts.
They have also never before beaten Wales in Cardiff after being behind at half-time, but they showed immense character to both upset the pre-match odds and recent history.
Wales tore into England from the start, accelerating into a 10-point lead before England had caught breath through Halfpenny’s long-range penalty and Rhys Webb’s try, the scrum-half skipping into the right-hand corner after Taulupe Faletau had peeled away from a retreating Welsh scrum on the visitors’ five metre line.
England hit back, Watson racing onto Mike Brown’s grubber kick into the corner to gather and dive over for his first Test try, and despite Ford’s missed conversion there was suddenly hope for the men in white.
In a frantic, febrile atmosphere Halfpenny and Ford exchanged penalties to make it 13-8 after half an hour, Dan Biggar stretching the lead to eight points with a long-range drop-goal just before the break.
The scoreline reflected both English indiscipline and Wales’ greater ruthlessness in the opposition 22, but it was England who struck first in the second period to blow the game wide open.
Wave after wave of bulldozing runs from their forwards dented the Welsh line, and as space opened up on the right Joseph spun out of one tackle and sliced between two other defenders with a dummy overhead pass to cross for his own first Test try.
Ford missed a long-range penalty that would have put England in front but the momentum appeared to be shifting.
Lancaster threw on Tom Youngs and Mako Vunipola for Dylan Hartley and Joe Marler and England’s heavyweight ball-carriers punched dents again.
James Haskell took the ball at pace from Youngs’ flat pass and looked certain to score, only for a combination of the post and Alex Cuthbert’s illegal work to hold him up short.
But Cuthbert was sin-binned and Ford stroked over the penalty from in front of the sticks to put English noses in front for the first time.
Errors crept in on both sides as the minutes slipped by and the tension mounted.
England thought they had that key score when Dave Attwood burrowed over with five minutes left, only for the television match official to rule it out for obstruction from replacement Nick Easter.
But then Ford landed another long-range penalty after good work from replacement Billy Twelvetrees, and Swing Low rang around the stadium at the final whistle as the men in white celebrated.
Wales: Halfpenny; Cuthbert, J Davies, Roberts, North; Biggar, Webb; Jenkins, Hibbard, Lee, Ball, AW Jones, Lydiate, Warburton, Faletau.
Replacements: M Phillips for Webb (69), James for Jenkins (60), Jarvis for Lee (72), Charteris for Ball (69), L Williams for North (26-34).
Not Used: Baldwin, Tipuric, Priestland.
Sin Bin: Cuthbert (61).
England: Brown; Watson, Joseph, Burrell, May; Ford, B Youngs; Marler, Hartley, Cole, Attwood, Kruis, Haskell, Robshaw, B Vunipola.
Replacements: Twelvetrees for Burrell (76), Wigglesworth for B. Youngs (69), M. Vunipola for Marler (55), T Youngs for Hartley (55), Brookes for Cole (62), Easter for Kruis (72).
Not Used: Croft, Cipriani.
Att: 74,500
Ref: Jerome Garces (France).