In a game littered with Lions stars on both sides, two-time tourist Vunipola delivered a relentless defensive display as the Red Rose triumphed 32-20 at the Aviva Stadium.
Vunipola – who played every Test on the Tours of Australia and New Zealand – finished the game having made 25 tackles as England got their campaign off to a winning start.
Fellow Lion Owen Farrell, also a two-time tourist, racked up 12 points with the boot while Elliot Daly – a tourist in New Zealand in 2017 – scored one try and assisted another.
First blood went to England with just two minutes on the clock when the Lions partnership of Farrell and Daly combined to put winger Jonny May over in the corner.
Farrell added the extras to give the visitors a perfect start before opposite number and fellow Lions star Johnny Sexton slotted a penalty to close the gap to 7-3.
The hosts then took the lead for the first time after Lions scrum-half Conor Murray’s initial dive for the line was rebuffed, with Cian Healy forcing his way over for Ireland.
Their lead did not last long, though, as Jack Nowell – who made two Test appearances on the 2017 Tour of New Zealand – forced an error from Jacob Stockdale to allow Daly to dot down.
Farrell converted again to restore England’s lead and, after Vunipola saw his try ruled out, the fly-half made the most of a penalty advantage to put the visitors 17-10 ahead at the break.
A Sexton penalty cut the deficit on 55 minutes, but England responded with their third try after Henry Slade latched on to a May kick over the Irish defence and finished superbly.
Farrell landed a further penalty just inside Ireland territory to extend England’s lead to 12, before Slade intercepted a Sexton pass to score his second of the game.
Substitute John Cooney, making his Six Nations debut, pulled one back for Ireland in the closing minutes but it was nothing more than a consolation as England held on for victory.
Ireland No. 9 Murray, a two-time tourist in 2013 and 2017, said: “We started slow and then we gave up a couple of soft tries and against a team of England’s quality you’re always going to be struggling.
“If you look at the end of the game we started chasing it and gave up another couple of soft scores, so I think our start killed us and you can’t do that against England.”
