Bird's-eye View Of Afghanistan

Muhammad Qasim Hindu Shah (Ferishta) explains extensively about Afghans in the 16th century. For example, he writes:
The men of Kábul and Khilj also went home; and whenever they were ques­tioned about the Musulmáns of the Kohistán (the mountains), and how matters stood there, they said, "Don't call it Kohistán, but Afghánistán; for there is nothing there but Afgháns and dis­turbances." Thus it is clear that for this reason the people of the country call their home in their own language Afghánistán, and themselves Afgháns.
By the 17th century AD, it seems that some Pashtuns themselves were using the term as an ethnonym - a fact that is supported by traditional Pashto literature, for example, in the writings of the 17th-century Pashto poet Khushal Khan Khattak:
Pull out your sword and slay any one, that says Pashtun and Afghan are not one! Arabs know this and so do Romans: Afghans are Pashtuns, Pashtuns are Afghans!