India formally recognises Bangladesh
India recognised Bangladesh on 6 December 1971 during the India–Pakistan war and Bangladesh’s liberation struggle. The date established formal bilateral ties and is jointly commemorated as Maitri Diwas.
Recognition on 6 December is distinct from the surrender in Dhaka on 16 December. This article does not imply that India alone created Bangladesh.
Source: Prime Minister of India: India–Bangladesh joint statement
War and the Bangladesh crisis transform South Asia
After mass violence and refugee flight from East Pakistan, India entered a war that ended with Pakistani forces surrendering in Dhaka and Bangladesh becoming independent. The conflict altered regional strategy and left complex memories across three countries.
Bangladesh’s liberation was driven first by Bengali political resistance and armed struggle. India’s military intervention was decisive in the final war, but it should not replace the agency or suffering of people in East Pakistan.
Source: Encyclopaedia Britannica: Bangladesh Liberation War