Treaty between Ahom commander Momai Tamuli Borborua and Mugal Subedar Allah yaar Khan
The Treaty of Asurar Ali established a fixed boundary between the Mughal Empire and the Ahom kingdom, ending over two decades of Mughal expansionist pressure into Assam.
Key Facts
- Date signed
- Early February 1639
- Northern boundary river
- Barnadi River
- Southern boundary
- Asurar Ali (Rajgarh Road, Guwahati)
- Mughal gain
- Western Assam from Guwahati to Manas River
- Preceding Ahom victory
- Duimunisila, November 1638
- Period of Mughal incursions
- 1615–1639
By the Numbers
Location
Cause → Event → Consequence
Beginning in 1615, the Mughal Empire made sustained efforts to extend its control into the Ahom kingdom of Assam. These efforts culminated in a decisive Ahom military victory over Mughal forces at Duimunisila in November 1638, which left the Mughals in a weakened negotiating position and compelled both sides to seek a diplomatic resolution.
In early February 1639, Mughal faujdar Allah Yar Khan and Ahom general Momai Tamuli Borbarua signed the Treaty of Asurar Ali. The agreement fixed the boundary between the two powers along the Barnadi River on the northern bank and the Asurar Ali causeway on the southern bank of the Brahmaputra. The Ahom king formally recognized Mughal supremacy in Kamrup, while the Mughals pledged non-interference in Ahom territory, and trade between the regions was officially permitted.
The treaty granted the Mughals formal control of western Assam from Guwahati to the Manas River, while securing the Ahom kingdom from further Mughal encroachment. The defined boundary provided a period of relative stability between the two powers, and the mutual recognition of territorial limits allowed regulated trade and diplomatic contact to proceed through designated representatives on both sides.
Political Outcome
Boundary fixed along Barnadi River and Asurar Ali; Mughals received western Assam; Ahom sovereignty east of the boundary recognized; mutual non-interference agreed.
Contested border region with ongoing Mughal military incursions into Ahom territory since 1615
Fixed boundary established; Mughals held Kamrup and western Assam; Ahom kingdom secured to the east