Explanation:

 Among the Chutiya kings was Gaurinarayan (Ratnadhwajpal), son of Birpal. He brought many other Chutiya groups into his kingdom. In 1224, Ratnadhwajpal defeated another Chutiya king named Bhadrasena, the king of Swetagiri, and conquered the area between Subansiri and Sissi rivers, i.e. present-day Dhemaji district. In 1228, he went on another campaign to further expand his kingdom and subjugate the Chutiya king Nyayapal (ruling the areas between Biswanath and Subansiri,i.e. present-day Biswanath and Lakhimpur districts) and marched toward Kamatapur, where he formed an alliance with the Kamata ruler by marrying a princess. Then he marched to Dhaka, and made friends with the Gauda ruler.