The Indo-Pakistani War of 1971, the third of four wars between India and Pakistan, took place in December 1971 and led to the creation of Bangladesh. This conflict was primarily over the issue of Bangladesh's independence.

The crisis began when the Pakistani army, dominated by Punjabis, refused to transfer power to the predominantly Bengali Awami League, led by Sheikh Mujibur Rahman. Rahman's proclamation of Bangladeshi independence in March 1971 was met with severe repression by the Pakistani army and pro-Pakistani Islamist militias, leading to widespread atrocities. From March 1971, it is estimated that between 300,000 and 3,000,000 civilians in Bangladesh were killed.^[42] Additionally, between 200,000 and 400,000 Bangladeshi women and girls were systematically raped in a campaign of genocidal rape.^[43] These events triggered a massive refugee crisis, with an estimated eight to ten million people fleeing to India for refuge.

The official war began with Pakistan's Operation Chengiz Khan, involving preemptive aerial strikes on 11 Indian air stations. These strikes resulted in minor damages and temporarily disrupted Indian air operations. In response, India declared war on Pakistan, siding with the Bengali nationalist forces. The conflict expanded to both the eastern and western fronts involving Indian and Pakistani forces.

After 13 days of intense fighting, India achieved dominance on the eastern front and sufficient superiority on the western front. The conflict ended on December 16, 1971, with the Eastern defence of Pakistan signing an instrument of surrender in Dhaka. This act officially marked the end of the conflict and led to the formation of Bangladesh. Approximately 93,000 Pakistani servicemen, including both military personnel and civilians, were taken as prisoners by the Indian Army.