After providing the free-kick that Mario Mandzukic headed into his own net to give France the lead in Moscow, Griezmann scored from the penalty spot to make it 2-1 following a contentious handball decision.
Paul Pogba and Kylian Mbappe added further goals after the break and while Hugo Lloris’ error gifted Mandzukic a chance to cut the deficit, Les Bleus held on win 4-2 in Moscow .
France’s triumph ends two years of scrutiny following their disappointing 1-0 loss to Portugal at the climax of Euro 2016 on home soil, as they lifted the World Cup for the second time in their history.
Asked about the different backgrounds of his team-mates after the game, Griezmann said: "That’s the France we love. Different origins but we are all united.
"In our team there are many players who come from different horizons, but we have the same state of mind.
"When we play for our jersey and our country we give everything we have. As soon as you wear the jersey we play together."
Griezmann was in the France team that missed out on glory two years ago, coming up short against an unfancied Portugal team, and he said Didier Deschamps' squad had worked on issues identified in the aftermath of that defeat.
CHAMPIONS DU MONDE. Vive la France pic.twitter.com/YI3bGeHr5e— Antoine Griezmann (@AntoGriezmann) July 15, 2018
He also paid tribute to the players who had joined the ranks since 2016, including key contributors Kylian Mbappe , Benjamin Pavard, and Lucas Hernandez.
When questioned about what they had learned from the Portugal result, Griezmann replied: "We did work on that. I don’t know how many players were at the Euros [that are in squad now], but we have had many changes.
"Some new players arrived and that was really good for us. They have brought added value to our teams.
"We are a whole group, who have lived together since the start. Substitutes were never in a mood – never annoyed. We’ve been working for the collective so everything would go well for us.
"The coach was right, he knew how to analyse matches. I'm really proud of this team."