A Guide to the United States' History of Recognition, Diplomatic, and Consular Relations, by Country, since 1776: India
In an unconventional sequence of events, the United States and India established diplomatic relations prior to India’s formal independence from the British Empire. The multistage independence process agreed to by the Indians and the British allowed for the creation of an interim government with the authority to conduct relations with other states before India attained full, sovereign independence.
U.S. Recognition of Indian Independence, 1947.
The United States recognized the Union of India as an independent state on August 15, 1947, when President Harry S. Truman sent a congratulatory message to Lord Louis Mountbatten, Governor General of the Dominion of India. It was on this date that, in accordance with the British Parliament’s India Independence Act of July 18, 1947, the Union of India and Pakistan were created from the former “British India” that had been a part of the British Empire.
The formal process that led to Indian independence began with a report that the British government issued on May 16, 1946, which recommended the formation of an interim government in India to devise a constitution as part of a process by which India would achieve independence from Great Britain. An Interim Government of India was formed on September 2, 1946, and this is the government with which the United States established diplomatic relations prior to formal Indian independence (see Diplomatic Relations below).
Establishment of Diplomatic Relations and the American Embassy in India, 1946.
Diplomatic relations and the American Embassy at New Delhi were established on November 1, 1946, when the U.S. Department of State raised the American Mission at New Delhi to an Embassy. The U.S. Department of State announced on October 22, 1946, that the Governments of India and the United States had “agreed to an exchange of ambassadors and to the raising of their respective missions…to the rank of embassies.”