In 1624 a new dynasty arose in the interior, when Nasir ibn Murshid of the Yariba (Ya`aruba) tribe (originally from Yemen) was elected imam and established his capital at Rustak.
The Mahrattas were in possession of the entire west and great part of the centre of the peninsula; while the rich and unwarlike province of Bengal, though governed by an hereditary line of nawabs founded by Murshid Kuli Khan in 1704, still continued to pour its wealth into the imperial treasury.
At the time of Aurangzeb's death in 1707 the nawab or governor of Bengal was Murshid Kuli Khan, known also as Jafar Khan.
Murshid Kuli Khan transferred his residence to Murshidabad, in the neighbourhood of Cossimbazar, the river port of all the Ganges trade.
Murshid Kuli Khan ruled over Bengal prosperously for twenty-one years, and left his power to a son-in-law and a grandson.