Which country came into existence after the Indo-Pakistan War of 1971?

The Indo-Pakistan War of 1971 was the direct military confrontation between India and Pakistan during the Bangladesh Liberation War in 1971. Indian, Bangladeshi and international sources consider the beginning of the war to have been Operation Chengiz Khan, when Pakistan launched preemptive air strikes on 11 Indian airbases on 3 December 1971, leading to India's entry into the war of independence in East Pakistan on the side of Bangladeshi nationalist forces, and the commencement of hostilities with West Pakistan. Lasting just 13 days, it is one of the shortest wars in history.

During the course of the war, Indian and Pakistani forces clashed on the eastern and western fronts. The war effectively came to an end after the Eastern Command of the Pakistani Armed Forces signed the Instrument of Surrender, on 16 December 1971 in Dhaka, marking the liberation of the new nation of Bangladesh. East Pakistan had officially seceded from Pakistan on 26 March 1971.