Kais
Kais the leader of the Afghan party that joined Muhammad in his mission as the Prophet of God about 622 A.D.
H. W. Bellew in book The Races of Afghanistan writes about the ancient history of Afghans. Here is page-wise account:
The traditions of this people refer them to Syria as the country of their residence at the time they were carried away into captivity by Bukhtunasar (Nebuchadnezzai), and planted as colonists in deficient parts of Persia and Media. (p.15)
This people was settled in the Ghor country, to the east of Herat, at the time that Muhammad announced his mission as the Prophet of God about 622 A.D. And it was there that Khalid-bin-Walid, a chief of the Curesh tribe of Arabs, came to them with the tidings of the new faith, and an invitation to join the Prophet's standard. (p.15)
Afghan people were originally of an Arab tribe, and had linked their fortunes with the Israelites in Syria, and shared the lot of the ten tribes which were carried away into captivity. The chief or leader Of this party was named Kais or Kish. (p.16)
Only some three or four hundred years ago that their priests began concocting genealogies and histories to give form and cohesion to the very mixed nationality. (p.16)
Sakistan, Sagistan, Sajistan, Sistan from the Saka, -who were probably the same people as the Saka Hamuvarga mentioned in the tables of Darius (see Rawlinson's Herodotus) "Saka dwellers on the Hamu" or Amu, which has from the earliest times been the name of the lower course of the Oxus river , the latter term being the Greek form of Wakhsh, which is the name of the Upper Oxus above the point where it is joined by the Panjah. (p.18)
The fictions of the Afghan genealogists and historians are absurd enough, and their facts wonderfully distorted ; but for the careful enquirer they have their value as guides to a right conclusion. Thus, from the Kais above-mentioned, whose own tribe was originally but an insignificant people as to numbers and power, the Afghan genealogists derive all the Pukhto-speaking peoples of Afghanistan, partly by direct descent, and partly by adoption on account of a similarity of language and social polity. (p.19)
Kais, they say, married a daughter of that Khalid-bin-Walid who brought his people the first tidings of the Prophet and his doctrine, and by her he had three sons, whom he named respectively, Saraban, Batan, and Ghurghusht. (p.19)
The Zamand were originally settled on the lower course of the Arghasan river and in Peshin or Foshang, as it was at that time 8-9 H or 630 A.D. called. They were subsequently ousted by the Tarin tribe of Afghans, and emigrated to Multan in large numbers. (p.19)
The Kansi early emigrated to Hindustan and the Dakkan, and are not now known in Afghanistan, though by some the Shinwari are supposed to belong to this division. (p.20)
These several tribes are divided into a number of clans and sub-tribes, the names of many of which are distinctly of Indian origin. The special Afghan tribe, however, is called Abdali, and is more commonly known since the time of Ahmad Shah the first independent sovereign of Afghanistan of this race by the name Durrani. The Durrani comprise the following chief divisions or clans, namely, Saddozai, Populzai, Barakzai, Halakozai, Achakzai, Nurzai, Ishaczai, and Khagwani. (p.20)
The Saddozai clan furnished the first independent Shahs, or kings, of the Durrani dynasty, and the Barakzai furnished the Amirs, or dictators. (p.20)
Jats in Afghanistan
And we know from the records of history that, apart from the transfer or displacement of populations consequent upon prior irruptions of Scythic hordes from the north-east, there took place about two centuries earlier, or during the fifth and beginning of the sixth of our era, a very powerful emigration of an Indian people from the western bank of the Indus to the valley of the Helmand and its tributary streams, towards a kindred people already settled there. (p.21)
This emigration en masse was owing, it would appear, to the irruption into the Indus valley of the Jats, and Katti, and other Scythic tribes, who about that period poured over the Hindu Kush. The Jats and Katti the Getes and Catti of European authors are now largely represented in this seat of their early conquest in the Jat (or Gujar as he is commonly styled) agricultural population of the Panjab, and in the Katti of Kattiwar or Kattiyawar. (p.21)
In Afghanistan the Jat is known by the name of Gujar, which is a Hindi term expressive of his calling as a rearer of cattle and a husbandman, and he is found in the greatest numbers in the Yusufzai country, especially in the hill districts of Swat, Buner, and Bajawar. (p.21-22)
This body of Indian emigrants, who migrated from the Indus to the Helmand, was composed of a people professing the Budhist religion, and who, fleeing away from the irresistible wave of Scythic invasion, abandoned their native country, and took along with them the most sacred and cherished relic of their spiritual lawgiver the water-pot of Budha. (p.22)
The Indian people who emigrated from the Indus and established themselves as a powerful colony on the Helmand were the Gandarii, and their country was the Gandaria of the Greek authors. They were the Gandhari, and their country the Sindhu Gandhara of the Hindu writers. (p.22-23)