Toony's troops may have had nothing at stake other than pride, but with Saints needing a bonus- point victory to make the last eight of the tournament, this victory ranks right up there as one of Glasgow's best in Europe.
In front of a throaty Scotstoun crowd of 4,193, Warriors racked up a last-gasp 27-20 victory that sends them into the three-week international break on a major high, with their next outing a trip to Italian side Zebre on Sunday, February 10.
Townsend said: "We needed this win to salvage some pride and I am very proud of it.
"Northampton came here looking for the bonus-point victory and tried to bludgeon us, but our forwards were immense and we matched them head-on.
"The winning try from Peter Horne was nothing short of sensational, so really this game had it all from us. Now we must use this victory as a platform to the final section of the PRO12 season and a real challenge for the title."
Toony was also delighted his men were able to repay the Warriors' faithful for their support.
He said: "The backing from the fans has been outstanding and we have finally managed to give them a win and a performance that repays them for all of that."
A brace of penalties from Ruaridh Jackson got Glasgow off to a flying start, but Saints pulled it back to 6-3 when Stephen Myler slotted home before Dom Waldouck ran over the line to give his side a 10-6 lead at the break.
Glasgow then hit back when a Josh Strauss try was converted by Scott Wight before Northampton went 15-13 up after George Pisi found a way through their defence.
The match then looked set to be tied after a converted Niko Matawalu try was cancelled out by five points from Ben Foden, but a fantastic solo try from Horne, which he then converted, sealed the late win for Glasgow.