Bengali Muslims are adherents of Islam among the Bengali people. The Muslims of Bengal are the second-largest ethnic Muslim community in the world. They speak the Bengali language and are native to modern-day Bangladesh and the eastern states of India, including West Bengal and Assam. Most Bengali Muslims are members of the Sunni branch of Islam. A minority are members of the Shia and Ahmadiya branches.The people of the Bengal Delta have multiracial origins, including a hybrid mixture of Indo-Aryan, Dravidian, Tibeto-Burman and Austronesian ancestry. The region was historically separated from India by the mighty Ganges and Brahmaputra rivers, allowing the Bengali people to develop an independent language and culture. The delta was a hub of trade routes, including Bay of Bengal and Indian Ocean trade; the Silk Road; and the Grand Trunk Road. Islam arrived in the first millennium and greatly influenced Bengali culture and civilization. The influx of Persian, Turkic, Arab and Mongol settlers further added to the rich cultural melting pot of Bengal. The Sultanate of Bengal was a major eastern frontier state in the medieval Muslim world. The Mughal Empire witnessed the further crystallization of Bengali Muslim identity. In the British Indian Empire, Bengali Muslims played a key role in developing modern political and artistic expression in South Asia. They compromised the demographic majority of East Pakistan, which became independent after a revolutionary liberation war in 1971.Bengali Muslims share strong cultural similarities with Bengali Hindus, Christians and Buddhists. Within wider Bengali culture, they have distinct social, linguistic and culinary characteristics. Bangladesh has a dominant Bengali Muslim-majority. They are the second largest community in the Indian states of West Bengal and Assam.