Despite facing some issues with his seat and tyres throughout the race, the reigning F1 champion led from start to finish comfortably crossing the line 18 seconds ahead of teammate Valtteri Bottas.
A virtual safety car in the final laps of the race set up an intense finish for second as Bottas held off a charging Charles Leclerc, but the Ferrari driver was unable to close the Finn down, finishing one second behind and rounding out the podium.
It was a day of mixed emotions for CAMS ambassador Daniel Ricciardo who finished just outside the top 10 after starting the race in eighth position.
A slow start for Ricciardo saw him drop to 10th, however, the West Australian managed to claw his way back into eighth thanks to solid moves on Red Bull’s Pierre Gasly and Haas’ Romain Grosjean.
Ricciardo got as high as seventh on the last lap, overtaking McLaren’s Lando Norris who was suffering hydraulics issues, only to be handed two five-second penalties post-race for dangerous overtaking, sending him down to 11th.
“The last lap was a lot of fun, we had a fight and I enjoyed it. I'd rather give it a go than not try at all, and I'm sure the French fans and the people at home liked watching," Ricciardo said.
"It's a shame to be penalised for it, but we'll aim to move on from that as quickly as possible.
“There are still a lot of positives to take and we will be looking for an immediate response in Austria.”
Hamilton’s victory continued Mercedes' unbeaten start to 2019, while Bottas’ second made six one-twos for German manufacturer this season, moving its lead in the Constructor standings to 140 points over Ferrari.
"It's definitely been a really good weekend,” Hamilton said.
“I couldn't do it without this incredible team, this group of guys here.
“We’re creating history together and I'm so proud of everyone, I’m so proud to be a part of this team, this group of people and Valtteri did a good job this weekend as well."
There is no break between races for Formula 1 crews with the next round taking place this weekend at the Red Bull Ring in Austria.