How did the Nazis figure out whether a person or community is 'Aryan' or not?

They used their “spidey sense”.

And then we get sexy time with them!

It was all bullshit the Nazis made up as they went along. Trying to cast it in real scientific terms is a waste of time.

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Ultimately, what made a group of people “Aryan” or not came down to how much they wanted them to be “Aryan”.

If the Nazis wanted someone to be “Aryan”, they made up some cock and Bull story to justify it. If they wanted the opposite, they could be equally inventive in assigning someone to “Untermensch” status.

Nazi racism was not actually scientific, it was just a load of bullshit with a thin patina of “science-y” garwharbl to justify what was basically a totally ideological belief.

Answer me this. These days guys love anal sex right, if you present them with your ass they will happily nail you into the ground. So why do some guys think it's "sissy" to let women stick a finger up their ass?

Ja, well, Helmut, it’s very simple. Those hot leggy blondes are actually not Slavs at all but are, in fact, Aryans who got Slavicised. We need to rescue them from the pit of subhumanism that surrounds them by immediately giving them Aryan status!

Poles are “ugly, subhuman Slavs” but hey, Hermann, have you noticed how hot and blond those leggy Polish chicks look? They don’t fit our “subhuman” model at all! İn fact, they kind of look like our Aryan ideal personified!

And then we get sexy time with them?

What are the reasons for your political affiliation with the Democratic party? What are some aspects of the party that you support and some that you do not?