Darrang
With the Mughals reaching the doorsteps of the Ahoms, hostilities ensued. These finally led to a large Mughal army attacking the Ahom kingdom in 1615-1616. On January 27, 1616, the Ahoms, under the king Pratap Singha, attacked the Mughals before dawn and massacred a major portion of the Mughal army. The Ahoms defeated the Mughals in the Bharali war and re-occupied Darrang from the Mughals. After the region was cleared of the Mughals, Pratap Singha established Bali Narayan, the brother of Parikshit Narayan, as the Raja of Darrang. Pratap Singha christened Bali Narayan as Dharma Narayan. The Ahoms, with the help of Bali Narayan, then moved against the remnant of the Mughals ruling in Hajo. After many battles the Ahoms and Bali Narayan's army finally conquered Hajo and removed their influence from Goalpara. Bali Narayan began his rule from Hajo.
This did not last for long and the Mughals maintained their attack on Koch Hajo. Beginning with 1637 the Ahoms faced a number of reverses, including the death of Bali Narayan in Singari battle in 1638. His son ascended the throne and became the king of Darrang (excluding Tezpur). On the other hand, the Ahoms ruled the eastern part of Darrang (the present Sonitpur) through Kalia Bhomora Borphukan, stationed at Kaliabor. In 1639 by the Treaty of Asurar Ali between the Ahom general Momai Tamuli Borbarua and the Mughal commander Allahyar Khan the river Barnadi was fixed as the boundary between the Mughal empire and the Ahom kingdom. Darrang remained with the Ahoms ruled by Mahendra Narayan, son of Bali Narayan. Mahendra Narayan was succeeded by Chandra Narayan and then by Surya Narayan.
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