The line comes from Joueur du Grenier, the long-running French YouTube series known for its loud, comedic reviews of retro games, in a special episode focused on Disney games. In that context, C'est la fête works as an exaggerated celebration, a moment where the presenter leans fully into the fun rather than the criticism. Clipped from the episode, it has circulated among French-speaking meme and gaming fans as a short reaction sound, and it endures because the phrase is simple, instantly understood and easy to drop into celebrations, victories and party-themed edits.