I don’t think OP is making jokes about surrendering, just referring to the period when France actually had a white flag.

However, white gradually became the pre-eminent royal and “French” colour, especially from the Hundred Years’ War onwards. By the later centuries of the monarchy, a plain white flag was widely seen – though never formally declared – as the personal emblem of the king and, by extension, of the French state itself.[1][2]. The tricolour flag, adopted during the Revolution and the Empire, was abandoned under the Restoration and replaced by a white flag, usually bearing the royal arms. It was itself abolished in 1830, and the tricolour was permanently restored.