The Aviva Premiership champions scored three times before the break – twice through North and once from George Pisi – to assert their dominance at Franklin’s Gardens.
North soon completed his hat-trick, with Luther Burrell (2), Kahn Fotuali’i and Jon Fisher each adding second-half scores.
And, as was so often the case last season, Stephen Myler was the glue that held the performance together, creative with ball in hand and accurate off the tee.
Despite a positive start from Northampton, hearts were in mouths early on as a crunching challenge left North under the attention of the hosts’ medical staff.
But he was soon on his feet and applying pressure on Charlie Sharples under the high ball – the Gloucester wing may have spilt the ball backwards but his side were awarded a scrum for knock-on.
Saints did, however, win a penalty from the scrum and Myler gladly accepted three points to break the deadlock.
Greig Laidlaw – on debut for Gloucester – had the opportunity to hit back just a minute later but his penalty came back off the crossbar.
Fellow debutant James Hook took over the kicking duties and levelled things up but North popped up just three minutes later to ensure parity didn’t last long, diving over to score in the corner.
Myler duly converted from the touchline but, not to be outdone, Hook attempted a 48-metre penalty only for his effort to fall short.
Pisi was next to pierce the Gloucester back line, collecting Myler’s perfectly-weighted chip to burst over before the creator added the extras.
Laidlaw then slotted his first penalty shortly before the break, but more clinical attacking rugby created Northampton’s third try on ten stroke of half time.
A side-step and spin took North clear of his marker before the Wales wing ducked over the line, Myler once more bisecting the posts.
They carried on after the break, collecting a bonus point when James Wilson streaked clear and offloaded to Burrell to bundle over by the corner flag.
Following a lengthy TMO decision the try was allowed and an immaculate conversion took the Saints 25 points clear.
North’s hat-trick arrived on 50 minutes, last of a huge Saints overlap on the left and gratefully accepting Myler’s looping missed pass, only for the fly-half to miss his first kick of the evening.
Fotuali’i came off the bench before the hour mark and soon skipped over the line to grab a try of his own.
But that wasn’t all from the replacements as Fisher benefitted from yet another overlap, coasting over and taking Northampton near a half-century of points.
And that half-century arrived five minutes from time when Burrell intercepted a sloppy offload and flew clear.
Northampton Saints 53 Gloucester Rugby 6