Bihari Muslims are adherents of Islam who identify linguistically, culturally, and genealogically as Biharis. They are geographically native to the region comprising the Bihar state of India, although there are significantly large communities of Bihari Muslims living elsewhere in the subcontinent due to the Partition of British India in 1947, which prompted the community to migrate en masse from Bihar to the dominion of Pakistan.

Purnia District is one of the thirty-eight districts of the Indian state of Bihar. The city of Purnia is the administrative headquarters of this district. The city of Purnia has continued its tradition of hoisting the national flag at 12:07 am on every Independence Day since 1947. Purnia district is a part of Purnia Division. The district extends northwards from the Ganges river.