The mountainous areas along the northern and eastern edges of the Indian Subcontinent are inhabited primarily by speakers of Tibeto-Burman languages.
Indigenous Tibeto-Burman-speaking communities are found through the northern, eastern, and especially the southeastern parts of Bangladesh, primarily the Chittagong Hill Tracts.
Due to the British colonization of the country, English is still a widely spoken and commonly understood language in Bangladesh.
Among the middle and upper class, many can read and write fluently due to professional requirements, but may have difficulty speaking English.
[9] Since the conquest of Bengal by Muhammad Bakhtiyar Khalji in 1203 CE, Arabic (عربي) enjoyed the status of being an official language up until the British Raj period.
In the 13th century, Muslim preacher Taqiuddin al-Arabi established what is thought to be the earliest Islamic institution in Bangladesh that has intact ruins.
Arabic literature began to flourish first in medieval Bengal with works like Ḥawḍ al-Ḥayāh (12th century) by Qadi Ruknuddin Samarkandi, Maqāmāt by Abu Tawwama, Majmūʿah Khānī fī ʿAyn al-Maʿānī (1280s) by Kamiluddin bin Karim as well as the many works of 14th-century Bengali scholar Nur Qutb Alam.
Islamic scholar Muhammad ibn Yazdan Bakhsh Bengali transcribed three volumes of Sahih al-Bukhari by hand in Ekdala, and gifted it to the Sultan Alauddin Husain Shah.
[10] Until today, Arabic literature relating to Islam continues to be regularly written and published by Bangladeshis such as Sultan Zauq Nadvi and Muhammad Abdul Malek.
Arabic is taught as a religious language in mosques, schools, colleges, universities and madrassahs as well as in tradition Bengali Muslim households.
[15] Presently, Persian is taught in some madrasas, mostly those belonging to the Befaqul Madarisil Arabia Bangladesh board, as well as at the University of Dhaka.