Modern Pakistan was created at 12 AM on 15 August 1947, when British India was replaced with two new states: the Dominion of Pakistan and the Union of India. The erstwhile British colony was divided along religious lines, with the Muslim majority regions in the East and Northwest going to Pakistan, and the Hindu majority regions going to India, in an event known as the Partition of India. As a result, Muslims in the new Union of India and Hindus from Pakistan migrated en masse to the other country. Over twelve million people moved across the new borders in the largest mass migration in human history. The migration was accompanied by massive outbreaks of inter-religious violence; estimates of casualties range from 500,000 to 1 million.
The movement for the partition of India and the creation of an independent Pakistan was spearheaded by a Lawyer named Mohammed Ali Jinnah. Jinnah believed that in a unified country with a Hindu majority, the interests of the Muslim population would be neglected.