Background story behind construction of Rohtas fort
Sher Shah threatened to construct such a fort in that country that it should not only effectually restrain the Ghakkars, but also the passage of the Mughals. He therefore himself made a tour through the hills of Girjhak Nlnduna [mountains circumjacent],‘ and finding a fit spot, he laid the foundations of the fort, which he called Rohtas.
Besides that, he sent a large force against Rai Sérang, the Ghakkar, and not only was the country subdued, and the hill of Balna'th plundered, which was then the residence of the Darogha of that tract, but the daughter of its chief was taken prisoner, and conducted before Sher Shah, who presented her to Khawas Khan; upon which Rai Sérang, they relate, sent a quantity of [hemp] blankets and millet to Sher Shah, with the remark that in such only consisted their raiment and food, besides which they could afford nothing; according to others, he sent a lion’s skin and some [arrows] spears, which he said was their only property. With this conduct, however, Sher Shah was by no means satisfied. Sarang [Sarang’s troops] being weakened by [skirmishes] the attacks of“ the holy warriors, and greatly reduced and straitened, submitted himself in person to Sher Shah, who ordered him to be flayed alive, and his skin to be filled with straw, and so pay the penalty of his misdeeds.
Sher Shah issued farma'ns to complete the fortifications of Rohtas ; but Todar Khatri represented that the Ghakkars, to whom that country belonged, would not allow any one to work for wages; and that they had agreed amongst themselves, upon oath, to expatriate every person that should contravene their wishes. Sher Shah, in answer, told him [that he should noways be allowed to give up that work, which he only wished to do in consequence of his greediness for gold] that the work did not seem to advance under his superintendence, and that a man who was fond of money, and was alarmed about disbursing it, would never accomplish the king’s designs. Todar, on the reception of this fresh command, fixed first a golden ashrafi as the enormous remuneration for one stone, which induced the Ghakkars to flock to him in such numbers that afterwards a stone was paid with a rupee, and this pay gradually fell to five tankas, till the fortress was completed." ’
The History of India as Told by Its Own Historians the Muhammadan ..., Volume 5 page 115