What is the significance of the rooster on the French jersey?

The Les Bleus are wearing their national symbol of a rooster at this World Cup, and it’s particularly poignant when facing England. For long signifying republicanism (as against monarchy), the symbol has been proudly crowing on their crest this edition.
“During the First World War, it was used as a symbol of France’s resance and bravery on the battlefield,” wrote talkSport of the golden rooster embossed on their royale matte blue jerseys.
“Its continued rise in prominence led to it remaining popular ever since and the rooster has continued as a symbol of modern France. It is now seen on all of the nation’s football and rug kits and it also features on postage stamps, war memorials and logos,” talkSport continued.

The rooster that appears on the French football shirt is called the Gallic Rooster, according to the website.
“It is a symbol that originated due to the old Latin name for France which is Gaul. This led to people from that region being called ‘Gallus’ which also means rooster in Latin.”

It began as a chuckle, treated as a joke for the people of France. “But it would eventually stick and French kings adopted the rooster as a symbol of courage and bravery. Its use then became even more widespread after the French Revolution. It was seen as a symbol of the people who founded the country and as the republicans rejected a royal narrative in preference of France’s true roots, the rooster rose to prominence as a symbol to represent the country’s origins,” talkSport wrote.

The French have looked good this World Cup, and there’s no bigger name than Kylian Mbappe to trip up the English. He resumed training with the team after a solo indoor practice on Tuesday. Didier Deschamps’ coaching team trained on defensive setpieces according to L’equippe.