Farid was soon taken to Sasaram by his father, Hasan, who had been granted a jagir there by his master, Umar Khan Sarwani, entitled Khan-i-A’zam, when the latter got the governorship of Jaunpur. Hasan, like the other nobles of his time was a polygamist, and Farid’s step-mother had predominant influence -over him. This made him indifferent to Farid whereupon the latter left home at the at of twenty-two and went to Jaunpur. Thus the Afghan youth was forced into a life of adventure and struggle, which cast his mind and character in a heroic mould.
On the death of his father, Farid took possession of his paternal jagir on the strength of a royal firman, which he had been able to procure at Agra. In 1522 he got into the service of Bahar Khan Lohani, the independent ruler of Bihar, whose favour he soon secured by discharging his duties honestly and assiduously. His master conferred on him the title of Sher Khan for his having shown gallantry by killing a tiger single-handed, and also soon rewarded his ability and faithfulness by appointing him his deputy (Vakil) and tutor (Ataliq) of his minor son, Jalal Khan.
But perverse destiny again went against Sher. His enemies poisoned his master’s mind against him, and he was once more deprived of his father’s jagir. “Impressed by the complete success of Mughul arms ” and with the prospect of future gain, he now joined Babur’s camp, where he remained from April, 1527, to June, 1528. In return for the valuable services he rendered to Babur in his eastern campaigns, the latter restored Sasaram to him.
Sher soon left the Mughul service and came back to Bihar to become again its deputy governor and guardian of his former pupil, Jalal Khan. While the minor king remained as the nominal ruler of Bihar, Sher became the virtual head of its government. In the course of four years he won over the greater part of the army to his cause and “elevated himself to a state of complete independence’. Meanwhile, the fortress of Chunar luckily came into his posession. Taj Khan, the Lord of Chunar, was killed by his eldest son, who had risen against his father for his infatuation with a younger wife, Lad Milika. This widow, however, married Sher Khan and gave him the fortress of Chunar. Humayun besieged Chunar in 1531, but Sher Khan had taken no part in the Afghan rising of that year and saved his position by a timely submission to the Mughul invader.
The rapid and unexpected rise of Sher at the expense of the Lohani Afghans made the latter, and even Jalal Khan, impatient of his control. They tried to get rid of this dictator. The attempt, how ever, failed owing to his ” unusual circumspection”. They then entered into an alliance (September, 1533) with Mahmud Shah, the King of Bengal, who was naturally eager to check the rise of Sher, which prejudiced his own prestige and power. But the brave Afghan deputy inflicted a defeat on the allied troops of the Bengal Sultan and the Lohanis at Surajgarh, on the banks of the Kiul river, east of the town of Bihar (1534). The victory at Surajgarh was indeed a turning-point in the career of Sher. “Great as it was as a military achievement, it was greater in its far-reaching political result…… But for the victory at Surajgarh, the jagirdar of Sasaram would never have emerged from his obscurity into the arena of politics to run, in spite of himself, a race for the Empire with hereditary crowned heads like Bahadur Shah and Humayun Padshah. ” It made him the undisputed ruler of Bihar in fact as well as in name. Sher had an opportunity to increase his power when Humayun marched against Bahadur Shah of Gujarat.
Humayun, who was then whiling away his time in idleness and festivities at Gaur, was disconcerted on hearing of Sher’s activities in the west and Ieft Bengal for Agra before his return should be cut off. But he was opposed on the way, at Chaunsa near Buxar, by Sher Khan and his Afghan followers and suffered a heavy defeat in June, 1539. Most of the Mughul soldiers were drowned or captured; and the life of their unlucky ruler was saved by a water-carrier, who carried him on his water-skin across the Ganges, into which he had recklessly jumped.