I think they would generally have agreed with the Nazis that certain groups of people shared certain characteristics
Especially it seems that Ancient writers liked to attribute certain physical appearance to entire groups of people.
From some of those Ancient texts it appears, that entire tribes were literally "clones" of identical-looking people.
For example - Herodotus:
"(...) The Budini for their part, being a large and numerous nation, is all mightily blue-eyed and ruddy. (...) Above the Sauromatae, possessing the second region, dwell the Budini, whose territory is thickly wooded with trees of every kind. The Budini are a large and powerful nation: they have all deep blue eyes, and bright red hair. (...) Their country is thickly planted with trees of all manner of kinds. In the very woodiest part is a broad deep lake, surrounded by marshy ground with reeds growing on it. Here otters are caught, and beavers. (...)"
And, IIRC, Celts who invaded Rome under Brennus were described as very tall "giants" with blue eyes (I might be wrong about blue eyes).
And later the Teutones, the Ambrones and the Cimbri, were also described as all - no exceptions - being "giants" with blue eyes (like above).
Also Procopius of Caesarea (500 - 565 AD) wrote this about Slavic tribes:
Nay further, they do not differ at all from one another in appearance. For they are all exceptionally tall and stalwart men, while their bodies and hair are neither very fair or blond, nor indeed do they incline entirely to the dark type, but they are all slightly ruddy in color.
So it seems that all enmies of the Roman Empire and / or the Byzantine Empire were always described as "exceptional giants".
And of course, once again we have the "they do not differ at all from one another" claim.
And they all had brown / dark blond hair ("slightly ruddy") according to Procopius, as we can see. But, if we check other authors, then we can see them describing Slavic people as "all having blond hair" or even "all having dark hair". For example in Muslim sources the following could be found:
The earliest Arabic sources describe the Slavs as a people with pale skin, that turns "red" while under the sun, and blond hair.
Another source describes Slavic people in Bohemia as having dark hair (except for some of them, who were blond).
So sources mention all existing hair colours among the Slavs, but each single source mentions only one...
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Back to Budini:
About the Budini writes also Pliny the Elder, contrasting them with dark-haired Agathyrsi (but at least he doesn't write that ALL of them are dark-haired - the fact that there is such thing like "typical appearance" of a certain group doesn't mean that all are clones).
Pliny the Elder:
The coast of the Sea of Azov, from the place called Taphrae at the end of the isthmus to the mouth of the Straits of Kertsch measures altogether 260 miles. After Taphrae, the interior of the mainland is occupied by the Auchetai and the Neuroi, in whose territories respectively are the sources of the Hypanis (the Southern Bug) and the Dnieper, the Geloni, Thyssagetae, Budini, Basilidae and Agathyrsi, the last a dark-haired people; above them are the Nomads and then the Cannibals, and after Lake Buces above the Sea of Azov the Sauromatae and Essedones. Along the coast, as far as the river Don, are the Maeotae from whom the sea receives its name, and last of all in the rear of the Maeotae are the Arimaspi. Then come the Ripaean Mountains and the region called Pterophorus, because of the feather-like snow continually falling there;
And Ammianus Marcellinus - he also provides interesting info on how various ethnic groups were often formed (in this case the Alans):
I am talking about the
"incorporation [of others] under their own national name":
The Hister (the Danube), filled to overflowing by a great number of tributaries, flows past the Sauromatians, and these extend as far as the river Tanaïs (the Don), which separates Asia from Europe. On the other side of this river the Halani (the Alans), so called from the mountain range of the same name, inhabit the measureless wastes of Scythia; and by repeated victories they gradually wore down the peoples whom they met and like the Persians incorporated them under their own national name. Among these the Nervii (the Neuri) inhabit the interior of the country near the lofty, precipitous peaks nipped by the north winds and benumbed with ice and snow. Behind these are the Vidini (the Budini) and the Geloni [the Geloni were also mentioned already by Herodotus], exceedingly savage races (...) On the frontier of the Geloni are the Agathyrsi, who checker their bodies and dye their hair with a blue colour - the common people with a few small marks, but the nobles with more and broader spots of dye. Beyond these are the Melanchlaenae and the Anthropophagi, who according to report lead a nomadic life
Once again someone translated as "races" what should be translated as tribes, etc.
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And Medieval Saxon chronicler Helmold von Bosau (1120 - 1177) wrote about Old Prussians:
(...) Prussians have not yet recognized our faith, but they have many natural qualities: they are very humane towards fellow creatures who find themselves in a hard situation, because they set sail to rescue those who get missing at sea and those who are harmed by pirates; they give aid to such people. They do not value gold and silver, but they have exotic fur coats in abundance, smell of which causes the deadly poison of pride in our world. And they consider these furs as worthless as manure (...) This is why in exchange for woolen clothes, which we call faldones, they give us such precious hides of martens. We could say many praiseworthy things about customs of these people, if only they were believers of the only faith of Christ; but quite the contrary, they are savagely persecuting all missionaries of this faith. It was in their country where famous Czech bishop Adalbert embelished his forehead with a martyr's crown. Until our times, when foreigners visit their lands, they allow such foreigners to live among them, but refuse them access to forests and springs. Because they think that presence of Christians in such places causes their profanation. (...) These people have blue eyes, red faces and long hair. (...)
Red faces...
Typical Prussian must be this guy (except for long hair):
http://trialx.com/curebyte/2012/08/26/pictures-for-red-face/
