The history of independent India began when the country became an independent nation within the British Commonwealth on 15 August 1947. Direct administration by the British, which began in 1858, affected a political and economic unification of the subcontinent. When British rule came to an end in 1947, the subcontinent was partitioned along religious lines into two separate countries—India, with a majority of Hindus, and Pakistan, with a majority of Muslims. Concurrently the Muslim-majority northwest and east of British India was separated into the Dominion of Pakistan, by the partition of India. The partition led to a population transfer of more than 10 million people between India and Pakistan and the death of about one million people. Indian National Congress leader Jawaharlal Nehru became the first Prime Minister of India, but the leader most associated with the independence struggle, Mahatma Gandhi, accepted no office. The Constitution adopted in 1950 made India a democratic country, and this democracy has been sustained since then. India's sustained democratic freedoms are unique among the world's newly independent states.

The nation has faced religious violence, casteism, naxalism, terrorism and regional separatist insurgencies. India has unresolved territorial disputes with China which in 1962 escalated into the Sino-Indian War, and with Pakistan which resulted in wars in 1947, 1965, 1971 and 1999. India was neutral in the Cold War, and was a leader in the Non-Aligned Movement. However, it made a loose alliance with the Soviet Union from 1971, when Pakistan was allied with the United States and the People's Republic of China.