High Quality Content by WIKIPEDIA articles! Sylheti is the language of Sylhet, which is also known as the Surma Valley and is located in the north-eastern region of Bangladesh, and also spoken in parts of the North-East Indian states of Assam (the Barak valley) and Tripura (the North Tripura district). It is also spoken by a significant population in the other north-eastern states of India and amongst the large expatriate communities in the United Kingdom, United States, and countries of the Gulf States.