\n\n“to take a French leave” (to leave a party or other gathering without taking polite leave of one\u2019s host) is referenced in French as filer \u00e0 l\u2019anglaise (lit. \u201cflee English-style\u201d).
In slang, sexual acts and diseases are *consistently* attributed to another nationality. Like in modern American English, you have *French* kissing (and historically, “French letters” for condoms), anal sex is called “Greek” and titty-fucking “Russian”.
IIRC at some point every country in Western Europe referred to syphilis as “The (X) Disease”, where X was a different foreign demonym.
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