Sher Khan Sur was born around 1486 into a family of Afghan jagirdars in Bihar. Rising through service, he defeated the Mughal emperor Humayun at Chausa in 1539 and Kannauj in 1540 and drove him out of India.
As Sher Shah he ruled for only five years but transformed the government of north India. He reorganised land revenue, introduced the silver rupee, and rebuilt the great road from Sonargaon in Bengal to the Indus, with caravanserais and wells every few miles; it became the Grand Trunk Road. To hold the Punjab against the Gakhars and the returning Mughals, he built the huge fort of Rohtas near Jhelum.
He was killed in 1545 when a gunpowder store exploded during a siege. Humayun returned ten years later, but Sher Shah's administration became the model for Akbar's.