A deafening chorus of "We are the champions, We are the champions" rang out from the Sacre Coeur in the north of the city to the Sorbonne on the Left Bank. Similar scenes erupted in Marseille, Lyon, Lille, Bordeaux and other major cities.
Even before the final whistle, crowds streamed on to the Champs Elysees, the elegant, tree-lined boulevard that runs up to the Arc de Triomphe, the traditional gathering place for celebration, including the Bastille Day parade 24 hours earlier.
The entire area around the Arc de Triomphe, all the way down the two-kilometre-long Champs Elysees and the Place de la Concorde at its end was a sea of singing and cheering people.
"It's just astonishing what they've done," said Josh, 41, who travelled from Brittany to Paris to watch the match with his girlfriend. "Pogba, Mbappe, Grizou (Griezmann) -- they're on top of the world," he said, naming three of the standout players.
"We're the champions of the world! It's phenomenal, just phenomenal."
More than 250,000 people were expected to descend on the Champs Elysees and the Place de la Concorde, yet the atmosphere was warm and convivial. Security forces kept a distance.
"To get a second star (World Cup) after 20 years, it's just brilliant," said Tommy Hamon, 23, who was working in Le Deauville, a bar on the Champs Elysees.
Even football fans who were not rooting for France but found themselves in the French capital for the game were overcome by the occasion and the scenes of celebration.
"France was not my team but I am so pleased for them today," said Sarah, a 24-year-old from Birmingham in England who is studying medicine in Paris.
"The players just showed something special all along, something that I liked, and I was not sure they would win today but they did. A lot of people are going to be drunk, if not already."
In Moscow, where tens of thousands of fans travelled to watch the game, there were tears of joy among the sea of red, white and blue. President Emmanuel Macron, who travelled to Moscow to watch the final with his wife Brigitte, hugged the players after the win and stood with them in the pouring rain.
As the World Cup trophy was brought on to the pitch for the victory ceremony, Macron briefly kissed it and beamed with joy.
“It was a great trip,” said Sebastien Mefort, 33, smiling broadly at Moscow's Luzhniki Stadium, his face painted the colours of the French flag. “I was here the whole month and attended all France’s games.”
Other fans expressed relief.
“We were worried about the result because Croatia plays very aggressive football," said Sylvie Wahl, 55. "But our coach and young players did it!”
Despite the deluge of rain that struck Moscow right after the game ended, fans danced and sang in the streets and a fireworks display could not be snuffed out.
France coach Didier Deschamps was full of praise for his team despite signs of nerves at the start of the game and several missed opportunities during it.
"It is really beautiful. It is marvellous. We did not play a great match, but we showed a strong mental quality," Deschamps said.
"We also scored four goals. We merit it. I am very happy for this team. We are coming from very far and it has not always been easy, but thanks to hard work, they are here and are on top of the world for the next four years."
(Additional reporting by Sudip Kar-Gupta and Bate Felix; Writing by Luke Baker; Editing by Ed Osmond) ((email@example.com; +33 01 49 49 51 30; Reuters Messaging: firstname.lastname@example.org))