Bundesliga: Gladbach 3 Borussia Dortmund 1
Monchengladbach suffered a shock DFB-Pokal exit at the hands of third-tier Arminia Bielefeld in midweek, but Lucien Favre's side made the perfect start on Saturday when Wendt fired them ahead after just 28 seconds.
And their lead was doubled just after the half-hour mark – reported Manchester United target Herrmann surging forward at blistering pace before teeing up Raffael to slot into an open goal.
Shinji Kagawa squandered two chances in quick succession as Jurgen Klopp's men - beaten by Bayern Munich last time out - appeared rejuvenated after the interval.
Those misses proved costly just over 10 minutes later, Havard Nordtveit scooping in from close range following poor Dortmund defending from a corner.
Ilkay Gundogan did restore some pride for the visitors with a well-taken goal in the 77th minute, but Monchengladbach held firm to extend their unbeaten league run to eight games.
It was the hosts who raced ahead inside the opening minute.
Following good combination play with Raffael, Herrmann carved through Dortmund's defence before squaring to Fabian Johnson, who had replaced Thorgan Hazard in the starting line-up.
Though the United States international's shot was well saved by Roman Weidenfeller, Wendt – charging in from outside the area – was on hand to fire home the rebound.
Dortmund, once again shorn of injured star forward Marco Reus, did go close to restoring parity 15 minutes in, Henrikh Mkhitaryan's ambitious effort going just wide of the left-hand upright.
And the visitors' troubles were compounded after 32 minutes, Hermmann once again the catalyst for another sweeping move as he charged through the heart of the defence after picking up possession inside his own half.
The dynamic winger raced past the floundering Neven Subotic and, as Weidenfeller rushed out to close him down, calmly picked out Raffael, who duly netted his ninth league goal of the campaign.
After Weidenfeller had made a good save from Herrmann, Dortmund finally managed to get in behind Monchengladbach five minutes after the restart – Marcel Schmelzer making headway down the left before crossing to Kagawa, but he failed to tap home from close range.
Kagawa was guilty of missing another gilt-edged opportunity two minutes later, this time after being set up by Jakub Blaszczykowski, but the midfielder once again failed to tuck in the cross.
Monchengladbach should have extended their advantage when Raffael setting up Wendt in the box, but the left-back skewed his strike wide.
However, they did not have to wait much longer for a third – Nordtveit on hand to tap home after Sebastian Kehl had headed the ball into the back of second-half substitute Adrian Ramos.
Klopp introduced Jeremy Dudziak in place of Schmelzer with 20 minutes remaining, and the youngster did well to find Gundogan, who drilled a low effort past Yann Sommer to give the visitors some hope.
Max Kruse went close to adding a fourth for Monchengladbach, but the forward failed to nudge in Herrmann's cross, though that miss made little difference as they ended Dortmund's five-match unbeaten streak on the road.