Partition of India
The Partition of India divided British India into the countries of India and Pakistan (East and West Pakistan) in 1947. That was part of the end of British Raj, British rule in the Indian subcontinent. One reason for partition was the two-nation theory, which was presented by Syed Ahmed Khan and stated that Muslims and Hindus were too different to be in one country. Pakistan became a Muslim country. India became a majority Hindu country and became a nominally secular country in 1974 when the word "secular" was added to the Preamble of the Indian Constitution.