Your assertion that Pakistanis and Indians are routinely mistaken for one another is flawed and patently incorrect, except among those westerners who are perhaps uneducated.
The Persian and Greek scholars knew about differences between the different tribes thousands of years ago. Those differences have persisted throughout history under various guises and manifestations. Some have been willing to become civilised and organised, while others have not.
Indeed, Herodotus wrote specifically on the
distinct differences between the different ancient tribes of the Indian subcontinent (post the collapse of the IVC and the arrival of the Aryans).
Those who lay in the Indus Valley and to its west (I.e. modern day Pakistan and Afghanistan) were variably described as war like, gold miners, and the most financially productive satrapies of the Achaemenid empire.
Those who lay further to the east were known for the following observations in Herodotus' works:
"
Other Indians, to the east of these, are nomads and eat raw flesh. They are called Padaians (Padaioi). It is said to be their custom that, when anyone of them (whether man or woman) is sick, a man’s closest friends kill him saying that he will be lost to them as meat if he is wasted by disease. Though he denies that he is sick, they will not believe him, but kill and eat him. (2) When a woman is sick, she is put to death (like the men) by the women who are her close acquaintances. They sacrifice anyone who reaches old age and feast on his flesh. But not many of them reach old age, for the Padaians kill everyone who gets sick before that time."
"Other Indians have the following different custom: they neither kill anything that has life, nor sow anything, nor are they wont to have houses, but they live upon herbs, and they have a grain the size of millet in a pod, which springs spontaneously from the earth. This they gather, and boil it and eat it with the pod. When any one of them falls into any disorder, he goes and lies down in the desert, and no one takes any thought about him, whether dead or sick [Herodotus is probably talking here about
Brahmins, ancient Hindu ascetics, who were strict vegetarians]."
"These Indians whom I have described
have intercourse openly like cattle. They are all black-skinned, like the Ethiopians. (2) Their semen too, which they ejaculate into the women, is not white like other men’s, but black like their skin and resembles in this respect that of the Ethiopians.
These Indians dwell far away from the Persians southwards, and were not subjects of king Darius."
Herodotus of Greece, the “Father of History”, had a most vague and meagre knowledge of the Indian subcontinent. He knew that it was one of the remotest provinces of the Persian Empire t…
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