Union of India, also known as the Indian Union or Dominion of India, was a precursor to the present form of India. It was an independent state which existed during the period 15th August 1947 and 26th January 1950. Although the Union of India was converted into the Republic of India on 26th January 1950, by proliferation of the Constitution of India, the term "Union of India" or merely "the Union" is used even at the current age by the Indian judicial system in order to refer to the Government of India, also referred to as the Central Government and does not denote the local governments of the individual Indian states.
After the rule of the British Empire in India ended in the year 1947 and the country achieved independence, 2 separate two dominions were formed that succeeded the former British India, namely the Dominion of India and the Dominion of Pakistan. These two countries were attained the status of self-governing and autonomous units. These dominions were formed by the Indian Independence Act 1947 that was enacted and implemented by the British parliament, formally known as Parliament of the United Kingdom of Great Britain and Northern Ireland, which is the supreme legislative body in the United Kingdom, British Crown dependencies and British overseas territories. The new dominions of the former British India existed until the promulgation and circulation of the later republican constitutions, when it was replaced by the Republic of India.
During the period of the existence of the Union of India, the monarch of the British Empire acted as the Head of State of both the newly created and independent countries. Moreover a Governor General represented each of the dominions of India and Pakistan. But the Governor Generals did not act as designated Viceroys, which was a custom in the former British India.
During the existence of the Union of India or the Dominion of India, two Governor Generals held office in the Indian Union, namely-
* Louis Mountbatten, 1st Earl Mountbatten of Burma, from 1947 to 1948
* Chakravarti Rajagopalachari 1948 to 1950
Throughout this dominion period, Jawaharlal Nehru acted as the Prime Minister of India and held office. He was also the Head of Government of the Union of India.