Did @ncert mention that the Ahom ruler Chakradhwaj Singh of Assam fiercely defeated the Turkish Khilji invaders around 1206 CE?
This historical event is documented in Sanskrit on the Kanai Barsai stone inscription.
Sukaphaa, the Tai group's leader, and his 9000 followers founded the Ahom kingdom (1228-1826 CE), which ruled over much of the Brahmaputra Valley in modern Assam until 1826