Evidence suggests that an Indo-Aryan population entered the territory between 3,000 and 4,000 years back, and thus, the civilization has begun. The Mughal dynasty conquered the region in the 16th century. Following the waves of migration, the Portuguese, Armenians, French, and British have set their trade outposts in the territory. In 1757 the British force conquered the region, defeating Nawab Siraj-ud-Dwolla, the last Nawab of the Mughal dynasty. The 190 years of British rule concluded in 1947. Pakistan ruled the territory as East Pakistan from 1947 to 1971. Bangladesh becomes an independent country on 16th December 1971.