Explanation:

Naranarayan was the last ruler of the undivided Koch kingdom of Kamata. He succeeded his father, Biswa Singha. Under him the Koch kingdom reached its cultural and political zenith. Under his rule, and under the military command of his brother Chilarai, he was able to subjugate the entire Brahmaputra valley, including the Ahom kingdom; besides the Kachari, Tripura and Manipur kingdoms, as well as the Khyrem, Jaintia and others. This influence was halted when he faced Suleman Karranni of Bengal. He introduced a silver coin, called the Narayani, that greatly influenced the numismatics of Assam. He gave Srimanta Sankardeva the first royal patronage to Ekasarana Dharma.