The Nawabs
With the decline of Mughal empire, Patna moved into the hands of the Nawabs of Bengal, who levied a heavy tax on the populace but allowed it to flourish as a commercial centre. During 17th century, Patna became a centre of international trade.
The British started with a factory in Patna in 1620 for the purchase and storage of calico and silk. Soon it became a trading centre for saltpetre, urging other Europeans—French, Danes, Dutch and Portuguese—to compete in the lucrative business. Various European factories and godowns started mushrooming in Patna and it acquired a trading fame that attracted far off merchants. Peter Mundy, writing in 1632, calls this place, "the greatest mart of the eastern region".
Read more about this topic: History Of Patna