Majuli Island in Assam is the largest river island in India, located in the Brahmaputra River about 200 kilometers east of Guwahati. Formed by the changing course of the Brahmaputra and its tributaries, especially the Lohit River, Majuli once spanned 1,250 sq km. However, due to constant erosion, the island's area has now reduced to around 557 sq km.

The island is predominantly inhabited by tribal communities such as the Mishing, Deori, and Sonowal Kacharis. Assamese, Mishing, and Deori are the major languages spoken on the island. Majuli consists of 23 villages, with a population of approximately 150,000 and a population density of 300 persons per sq km.