French Kiss origin

Why do people refer kissing as french kiss? Is it because the first people who started exploring kissing were the French? If it wasn't originated from France or by the French, why french kiss and not cuban kiss or russian kiss? I was curious and went on googling about it.

What i found out was that the specific origin is unknown and it dates from about 1920s. It might be derived from the idea that the French are sterotyped for anything dirty. Just like how people use phrases like "French letter" as condom or "Pardon my French" for apologising for bad language.... I am not sure about french fries though. I'll check that up later when i have the time.