Cabinet Mission (1946): Proposed a complex federal structure to keep India united while addressing Muslim League concerns; ultimately failed to secure agreement between the Congress and the League.
Direct Action Day (16 August 1946): Called by the Muslim League under Muhammad Ali Jinnah to press the demand for a separate Pakistan; led to widespread communal violence, especially the "Great Calcutta Killings."
Mountbatten Plan (June 1947): The last Viceroy, Lord Mountbatten, formulated the plan for the partition of British India into two independent dominions.
Indian Independence Act (1947): Passed by the British Parliament, providing for the creation of India and Pakistan as independent dominions from 15 August 1947. Cyril Radcliffe headed the boundary commissions that drew the partition lines (the "Radcliffe Line") for Punjab and Bengal, done hastily and with limited local knowledge, contributing to immense subsequent hardship.
Aftermath: Partition triggered one of the largest and most traumatic mass migrations in human history, with estimates of 10–15 million people displaced and widespread communal violence resulting in significant loss of life (estimates vary widely, commonly cited between several hundred thousand and up to two million deaths).
Integration of Princely States: Sardar Vallabhbhai Patel, as India's first Home Minister, along with civil servant V.P. Menon, oversaw the political integration of over 560 princely states into the Indian Union, earning Patel the title "Iron Man of India." The most contentious integrations involved Junagadh, Hyderabad (annexed via police action, "Operation Polo," in September 1948, against the Nizam), and Jammu and Kashmir (acceded to India in October 1947 under Maharaja Hari Singh amid the first Indo-Pak war, with the accession's terms remaining a subject of long-running dispute).