The result was only Town's second away win of the season, the last coming on the opening day of the season at Crystal Palace with the side having also gone eight games on the road without scoring.
But the Terriers took full advantage of some rash Watford defending and a first-half red card for Troy Deeney to score an emphatic victory, moving them up to 11th in the table.
"I think a lot of people didn't expect we are where we are at the minute," David Wagner said after the Vicarage Road win.
"We have to make ourselves independent from pundits' predictions. It is irrelevant for us.
"We are so humble and so calm. We know what size of club we are, our budget.
“It is not comparable with any other budget here in the Premier League.
"But we are ambitious. We say, 'trust in yourself, be focused'.
“So far the players have done very good but it's only the mid-point of the season, nothing more. We can improve."
On the match itself, the German head coach was delighted with the overall result and intensity of the performance.
“What pleases me is that we were able to transform the theory into practice on the grass," said David Wagner.
"I am very proud and satisfied - my players were fantastic and performed at their very best.
“They deserved this win; they were so brave on the ball and pressed them high.
“We were on the front foot and in their faces and kept them away from our goal and didn’t give them the chance to build up their fluid play.
"We haven't scored so many goals in the past and collected so many points so to be so strong mentally to be independent even after we have such a difficult away run, this is something extraordinary."
“There were so many great individual stories in this game, but for me the biggest story is this team performance.”
The only blot on Huddersfield's afternoon was Elias Kachunga being carried off on a stretcher in the first-half.
Town's boss said the striker had sustained a knee injury and admitted it looked serious with further tests expected next week.