Napoleon was well respected by his opponents (Russians and British). His time and even his losses could not start that joke.
During 3 or 4 centuries before Napoleon France was a formidable adversary to England, Spain and Austria.
During Crusades Frankish knights were the core and the most reliable part of the Christian armies.
After Napoleon up to the end of WWI France was considered solid empire building nation very capable of fighting.
First part of 100 years war went very bad for France, but to be honest, England at that time included large parts of French territories and when we read that English king defeated French general, large part of "English" forces were Frenchmen as well. Besides, France had drove English kings out of France at the end. It means that even 100 year war could not possibly start that joke.
I guess, that joke was started during WWII. France quickly lost that war to Germany and surrendered. Nazi felt themselves very comfortable in Paris while French government allied France with Germany. Nazi could use all French resources with complete French cooperation in their war against England USSR and USA. France had spent whole WWII as Nazi ally.
Luckily for anti-Nazi coalition, French troops did not fight well for Nazi during that war.
It is amazing that nation allied with Nazi and fighting allies was considered one of the allies at the end of the war.
Italy did more to defeat Nazi in WWII than France. Italian troops fought Germans for 2 years while French troops waited for orders from Vichi.
PS No, brave French volunteers (like Charles de Gaulle) who violated orders of the legitimate French government are not France. There were many Italian volunteers violating Mussolini orders as well.They did not change the fact that Italy was German ally for the first half of the war.