Meanwhile, Morgan Parra's side finally managed to get their act together and give Wales a warning that they mean to overturn their Six Nations defeat at Newport three months ago.
Parra, one of two full internationals in the French side, led his team in typical fashion as he snapped at the heels of his pack and the French look like being Wales's biggest obstacle to topping their Pool.
In North Wales, last season's runners-up in the IRB Under 19 tournament, South Africa, laid down their credentials In Pool B with a 108-18 drubbing of the USA that included 16 tries and 25 points from outside half Josias Ebersohn.
Last year's Under 19 world champions, New Zealand picked up where they left off in Belfast with a 48-9 triumph in Pool A over a highly competitive Tongan outfit. At half-time at Cardiff Arms Park in was only 10-9 to everyone's pre-tournament favourites, the young All Blacks, and anything seemed possible.
But after the break six tries made the game safe for New Zealand as they got back some of the fluency they displayed last year.
There was also a big opening night win for Australia in Pool C at Newport's Rodney Parade, where they beat Canada 81-12. There were 13 tries for the young Wallabies and 20 points for their fullback Dane Haylett-Petty.
The Six Nations champions, England, took the hint from the Aussies and ran in six tries in a brilliant first-half burst against the Fijians that saw them race into a 41-0 interval lead. The Worcester Warriors wing Miles Benjamin ran in two of them, Saracens flyer Noah Cato got another and there was one from Seb Stegmann to complete the work of England's explosive back three.
The bewildered Fijians got to grips with the pace of the game in the second half and, as England Coach Nigel Redman range all seven possible changes, the remaining scores all came from Fiji as the game ended 41-17.
There was at least some joy for the Pacific Islands as Samoa came from behind against the Scots in Pool B to notch a famous 29-17 victory in Wrexham. Scotland were leading 10-9 at the interval, but then slipped 24-10 in arrears.
A try from Lee Jones brought the Scots back to within one score before wing Alatasi Tupou sealed victory for Samoa with a third try.
The Pumas proved too strong for the Irish in Pool A at the Arms Park, running out 17-9 victors with two tries to nil.
The next round of games is on Tuesday, when Wales take on Japan at the Liberty Stadium, New Zealand meet Ireland at the Arms Park and South Africa face Scotland at The Racecourse.