Conflict of Suteuphaa with Kacharis
Suteuphaa worked for the expansion of his kingdom and had developed hostile relationship with the Kacharis of the neighbouring region. During this period, Kacharis were the inhabitants of upper Assam and were forced to leave the region to the east of Dikhou River. The incident has been described in a historical document which states firstly Suteuphaa claimed the region as his own. This was initially opposed by the local folks but later both the parties decided to adopt a peaceful way of solving the conflict. Suteuphaa had challenged Kacharis to construct a canal within one night, from Dikhou River up to their settlement. Their agreement stated that if the construction completed within the allotted time, the region would belong to the Kacharis. However, the soldiers of Ahom kingdom played a trick and on the instructions of Suteuphaa, hided in the forest with roosters. When the canal construction was on the verge of completion, the soldiers made the roosters to cock. As the night was a full moon night, the Kacharis could not determine the time and were disguised by the cocking, believing that the night had passed. They left the region which was immediately captured by the Ahoms.
Conflict of Suteuphaa with Naras
When Shans or Naras of Mungkang were defeated in the war with the king of Mantara or Burma, they turned to Suteuphaa for help. Ahoms had always regarded the Naras or the Shans of Mungkang as their close kinsmen and communicated with each other as "Brother King" or "Bhai Raja". Suteuphaa, in response to their appeal for help, demanded to marry the daughter of the Nara king of Mungkang. The Nara king however refused the proposal which led to the initiation of a quarrel between the two. Consequently Suteuphaa sent his army, under the commandership of Burhagohain, against the Naras who were gravely defeated. Burhagohain was sent again for the second time, but couldn't succeed in defeating their enemy. On his return, he was imprisoned but intercession of other nobles set him free. However, according to some Ahom historians, no conflict occurred between Naras and Ahoms during the rule of Suteuphaa, instead this conflict took place during rule of Khora Raja or Sukhaamphaa.
In 1281 CE, Suteuphaa died and his throne was succeeded by Subinphaa, his eldest son. Suteuphaa's expeditions and applied tricks for the expansion of his kingdom were exemplary of his intelligence and wit, inherited from his father Sukaphaa, which were later followed by the succeeding kings of Ahom kingdom.