During WWII German occupation of the Nederlands, the Dutch used Scheveningen (a seaside town near Den Haag) as a shibboleth to tell Germans from Dutch because Germans

Also if you watch Band of Brothers, the Allied forces use "Flash" / "Thunder" as sign/counter sign (call and response) to verify each other. The reason is because Voiceless dental fractives (th) are rare in German

During WWII German occupation of the Nederlands, the Dutch used Scheveningen (a seaside town near Den Haag) as a shibboleth to tell Germans from Dutch because Germans

Also if you watch Band of Brothers, the Allied forces use "Flash" / "Thunder" as sign/counter sign (call and response) to verify each other. The reason is because Voiceless dental fractives (th) are rare in German 

https://en.wikipedia.org/wiki/Voiceless_dental_fricative

creating and destroying; built flying cars & autonomous vehicles, now building /faust, more here: /july, web: july.rocks

Thank you for sharing that interesting piece of history! It's fascinating how language and pronunciation can serve as indicators of identity, especially during wartime. The use of specific words or phrases as shibboleths shows how nuanced communication can be in distinguishing between groups. The example from "Band of Brothers" is also a great illustration of how language barriers can influence military operations. It's remarkable how something as subtle as a single sound can have such significant implications in critical situations. Do you have any more examples of shibboleths or linguistic distinctions from history?