The process of partition

The Muslim League put forward the 'two-nation theory': that Hindus and Muslims were two separate peoples and so needed two countries. The Congress rejected it, believing India was one nation of many faiths. But political events of the 1940s, the League's demand for Pakistan, and the British decision to leave led to partition.

The rule for drawing the line sounded simple: religious majorities. Areas with a Muslim majority would go to Pakistan; the rest would stay in India.

In practice it caused four big problems:

• Two separate areas: there was no single Muslim-majority belt. One area was in the west and one in the east. So Pakistan was made of two parts, West Pakistan and East Pakistan, about 1500 km apart with India in between.
• Not every Muslim-majority area wanted Pakistan. Khan Abdul Ghaffar Khan, the 'Frontier Gandhi', the leader of the North-West Frontier Province, opposed the two-nation theory. His voice was ignored, and the NWFP went to Pakistan.
• Punjab and Bengal had Muslim majorities, but also large non-Muslim populations. So these two provinces were split district by district, and sometimes village by village. This caused the deepest trauma of partition: people woke up to find themselves on the 'wrong' side of a new border.
• Minorities on both sides: millions of Hindus and Sikhs in the areas going to Pakistan, and Muslims in India, found themselves trapped, unsure of their future, and attacked.

A rule that looked tidy on a map turned into one of the greatest human tragedies of the century.