The Mountbatten Plan: How June 3 sealed the Partition of India
The Mountbatten Plan, announced on 3 June 1947 (also called the "June 3 Plan"), set out the mechanism by which British India would be partitioned into the two independent dominions of India and Pakistan.
Lord Louis Mountbatten, who had arrived as the last Viceroy of India in March 1947, presented the plan after earlier unity-based proposals (including the Cabinet Mission Plan of 1946) failed to secure agreement between the Congress and the Muslim League.
The plan advanced the transfer of power from the previously announced deadline of June 1948 to 15 August 1947, compressing preparation for the world's largest and most abrupt decolonisation transfer into about ten weeks.
Its provisions were converted into British law through the Indian Independence Act, 1947, passed by the British Parliament in July 1947.
The Mountbatten Plan (3 June Plan), 1947
The Mountbatten Plan was the political blueprint, announced by the Viceroy on 3 June 1947, that formalised the principle of partition along religious lines after the failure of the Cabinet Mission Plan's proposal for a united India with a loose federal structure. It provided that the Legislative Assemblies of Punjab and Bengal would each vote on whether to partition their province; if either group (Muslim-majority or Hindu-majority districts) voted for partition, the province would be divided. Sindh's Assembly would decide separately whether to join India or Pakistan, and the North-West Frontier Province's accession would be decided by a referendum. Should partition proceed, Boundary Commissions would be set up to demarcate the new frontiers.
Key Details
- The plan followed the collapse of the Cabinet Mission Plan (1946), which had proposed a three-tier federal structure to keep India united.
- Assam's Sylhet district (Muslim-majority, within a Hindu-majority province) was to hold a separate referendum on joining East Bengal.
- The Plan proposed two separate Constituent Assemblies for India and Pakistan, with each dominion governed under an adapted version of the Government of India Act, 1935, until its own constitution was framed.
The 3 June announcement is the specific event dated in the news; it is the political decision that triggered the drafting of the Indian Independence Act and the compressed ten-week transfer timetable.
Indian Independence Act, 1947
The Indian Independence Act, 1947 was the British statute that gave legal effect to the Mountbatten Plan. Passed by the British Parliament and given royal assent on 18 July 1947, it created two independent dominions, India and Pakistan, effective 15 August 1947, each free to leave the British Commonwealth, and ended British paramountcy over the princely states with effect from the same date.
Key Details
- The Act abolished the title "Emperor of India" for the British monarch and ended the office of the Secretary of State for India.
- It provided that until new constitutions were adopted, the Constituent Assemblies of each dominion would also function as their central legislatures, governed under the Government of India Act, 1935 as adapted.
- Paramountcy over roughly 565 princely states lapsed on 15 August 1947, leaving each state legally free to accede to India, Pakistan, or theoretically remain independent — the basis for the subsequent Instrument of Accession process.
The Act is the legal instrument through which the political terms of the 3 June Plan were enacted, converting the Mountbatten Plan's provisions into binding law within six weeks of the announcement.
The Boundary Commissions and the Radcliffe Line
Under the Mountbatten Plan, two Boundary Commissions, one each for Punjab and Bengal, were constituted to draw the new India-Pakistan border in these two provinces where the province itself was to be split. Sir Cyril Radcliffe, a British lawyer with no prior experience of India, was appointed common chairman of both commissions, each of which also had two members nominated by the Congress and two by the Muslim League.
Key Details
- Radcliffe arrived in India in July 1947 and was given roughly five weeks to demarcate borders affecting about 450,000 sq km of territory and an estimated 88 million people.
- The mandate was to divide contiguous majority areas of Muslims and non-Muslims, while also considering other factors such as communication networks and irrigation systems.
- The final boundary award (the Radcliffe Line) was kept unpublished until 17 August 1947, two days after independence, contributing to the chaos and large-scale displacement during Partition.
The Boundary Commissions were the direct implementing mechanism specified in the Mountbatten Plan for physically drawing the partition line in Punjab and Bengal.
- Mountbatten Plan announced: 3 June 1947; Indian Independence Act passed by British Parliament and received royal assent: 18 July 1947; transfer of power: 15 August 1947.
- Original power-transfer deadline (announced earlier by the British government) was June 1948; the Mountbatten Plan compressed this to about ten weeks.
- Radcliffe Line boundaries for Punjab and Bengal, chaired by Sir Cyril Radcliffe, were published on 17 August 1947.
- Paramountcy over approximately 565 princely states lapsed with the Indian Independence Act, 1947, requiring each state to accede via an Instrument of Accession.
- The Cabinet Mission Plan (1946), which preceded the Mountbatten Plan, had proposed a united India with a three-tier federal structure but failed to gain acceptance from both major political parties.