Eastern Indo-Aryan languages

The Eastern Indo-Aryan languages, also known as Māgadhan languages, are spoken throughout the eastern region of the Indian subcontinent, which includes Bihar, Uttar Pradesh, Jharkhand, Bengal region, Tripura, Assam, and Odisha; alongside other regions surrounding the northeastern Himalayan corridor.

Bengali is official language of Bangladesh and the state of West Bengal, Tripura and the Barak valley of Assam while Assamese and Odia are the official languages of Assam and Odisha, respectively.

[2][3][1] The exact scope of the Eastern branch of the Indo-Aryan languages is controversial.

The widest scope was proposed by Suniti Kumar Chatterji who included the Eastern Hindi varieties, but this has not been widely accepted.

It is suggested that "pre-Munda" ("proto-" in regular terminology) languages may have once dominated the eastern Indo-Gangetic Plain, and were then absorbed by Indo-Aryan languages at an early date as Indo-Aryan spread east.