The Mughals always had an eye on the Brahmaputra valley, even since the early 17th century. The first conflict between the Mughals and Ahom Kingdom (now Assam), which was part of the valley, began in 1615. The Mughals victory in this battle helped them rule part of the kingdom named Kamrup (now Guwahati and Hajo) for a while. After the fall of the Mughals empire under the reign of Shah Jahan, Pran Narayan of the Koch Bihar kingdom tried to occupy the Mughal-ruled Ahom. But the Ahom army recaptured the area by defeating Pran. During Aurangzeb’s period the Mughals took back Ahom. Later, Ahom army, strengthened under the leadership of Lachit Borphukan, won the battle of Saraighat ending the Mughal occupation of the kingdom.