East Pakistan, present-day Bangladesh, was a provincial state of Pakistan that existed in the Bengal region of the northeast of South Asia from 1955 until 1971, following the One Unit programme that laid the existence of East Pakistan.

East Pakistan had an area of 147,570 km2 (56,977 mi2). India bordered it on three sides (East, North, and West) with the Bay of Bengal to the South. East Pakistan was one of the largest provincial states of Pakistan, with the largest population, the largest political representation, and the largest economy. A nine-month-long war ended on 16 December 1971, when the Pakistan Armed Forces were overrun in Dhaka, ultimately signing the instrument of surrender which resulted in the largest number of prisoners of war since World War II. Finally, on 16 December 1971, East Pakistan was officially disestablished and was succeeded as the independent state of Bangladesh.

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