[9] Among these, Uttar Dinajpur is notable as ethnic Bengali Muslims comprise 28% of the district's population, with the remaining 22% being Urdu and Surjapuri speakers.

[12] The Sultanate's influence was expansive, with the Hindu-born sultan Jalaluddin Muhammad Shah funding the construction of Islamic institutions as far as Makkah Al Mukarramah and Madinah Al Munawwarah, which came to be known as al-Madaris al-Banjaliyyah (Bengali madrasas).

Sufis also became prominent in this period, such as Usman Serajuddin, also known as Akhi Siraj Bengali, who was a native of Gaur in western Bengal and became the Sultanate's court scholar during Ilyas Shah's reign.

Estimates show that 1,634,718 Muslim refugees from West Bengal settling permanently in East Pakistan during 1947–1951.

The Urdu-speaking Muslims from Bihar and Uttar Pradesh constitute rest 3%, numbering around 3 million and are mainly concentrated in Kolkata, Asansol, Islampur subdivision of West Bengal.