Found the article...Wow She agreed on the exact same conditions I myself predicted, too bad Marxist interpretation meant that she chose a different motivation for the stoppage of horse supply
http://www.columbia.edu/itc/mealac/pritchett/00islamlinks/txt_thapar_somnath.html
Highly highly highly indebted to you, thanks
I believe they are all mixed from three main sources .----->Aryans (as well as later Scythians and Central Asians), Western Asia Farmers, Ancestral South Indians
The Aryan component tend to be more or less same till Bihar among the upper castes...from around 28 percent in Pashtuns in Kabul to around 25 percent in Bhumihar Brahmins in Bihar
What really changes is the dosage of ASI component which becomes higher as you go into India, which suggests a higher population density of previously occuring ASI deep in the subcontinent
http://rpubs.com/anupampom/indusinter
http://rpubs.com/anupampom/steppeinter
http://rpubs.com/anupampom/aasi
The baove maps are data collated from the latest Reich harvard study for South Asian genetics
But even if there have been outside pulses, the culture of the subcontinent was developed in-situ
The Bharata Clan that sponsored the Rig Veda had it's home in Himachal and the home land of the various warring and allied Aryan tribes stretched from present Western UP to eastern rims of Afghanistan like Kabul...any place for east or west are regarded as known only to later Rig Vedic people (Rig veda being composed over around 600 years from 1700 BCE to 1100 BCE)...Even if the Aryans came from outside, by the time they composed the Vedas any memories of being outsider to the land was thoroughly lost...I am of the opinion Rig Veda and the extensive religious practices around it were developed a couple of hundred years after they entered Punjab and the Yamuna Sutlej stretch ....When they were entering the subcontinent, their religion may have been a bit simpler more akin to those of the Kalash than the complex Yajnas further east
This map by Schwartzberg gives the definitive rundown regarding the various Aryan tribes and homes of the Aryans during the composition of the Rig Veda
https://dsal.uchicago.edu/reference/schwartzberg/fullscreen.html?object=050
Every place West of Kabul would have firmly been in the grip of zoroastrianism or pre-zoroastrian Iranian religion..They would also much more readily available ephedra dystica or haoma/soma....with the Vedics either procuring them from Kashmir or through trade from Ancient Iranians
Of course there were later Achaemenids, Indo-Greeks,Indo-Parthians,Indi-Scythians,Kushanas,Indo-Sassanids,Hepthalites coming into the region...but they never left any long lasting cultural legacy..except the Scythians transforming themselves into some Jatt clans and the hepthalites into some Rajput clans...It is these Rajput clans who would play a significant role in the military history of the the North west portion of the subcontinent well after the Turkic invasions...that the Gakhar tribe assasinated Ghori may have inspired the author of Prithvirajraso to pen a fictional account (self-admitted) of a blind Prithviraj finally killing Ghori
Certainly the Chauhans would have felt some kinship to the son-of-the-soil fellow Rajputs
The Aryan pulse into the subcontinent left the lasting legacy of the Vedas
The Turkic pulse into the subcontinent left the lasting legacy of Islam..(prior to that Islam was confined to Sindh and lower Punjab for about 480 years)
The Hindu Shahis had their core troops from that region------>They resisted the full blown wrath of the Turks for 150 years...were n't exactly Phattus...Had the same honour based culture as the Rajputana Rajputs to the East..Anandapala (actually Jayapala) jumped into the fire after losing the Battle of Peshawar to Ghazni. A Phattu would have become a vassal...History needs to be seen on its own term during each period...Even 200 years later the Gakhar clan was fiercely resisting the Turks, resulting in the assasination of the famed Ghori...as great as the region of potohar was, it was just too small to face the combined Turkic might of Central Asia...but still they immortalized themselves...It would take a much longer struggle to match Central Asian cavalry tactics which eventually happened