It is celebrated in India every year on December 16.
It is to commemorate the victory of the Indian armed forces over Pakistan in the 1971 Indo-Pak War.
It is also known as the Bangladesh Liberation War.
The India-Pakistan war began on December 16, 1971.
It was one of the shortest wars (13 days) and saw one of the biggest surrenders.
On December 16, 1971, the Chief of Pakistani forces Abdullah Khan Niazi surrendered along with 93,000 troops to the allied forces of Mukti Bahini and the Indian Army.
Vijay Diwas is observed in Bangladesh as Bijoy Dibos.