The Dominion of India, officially the Union of India, was an independent dominion in the British Commonwealth of Nations existing between 15 August 1947 and 26 January 1950. Until its independence, India had been ruled as an informal empire by the United Kingdom. The empire, also called the British Raj and sometimes the British Indian Empire, consisted of regions, collectively called British India, that were directly administered by the British government, and regions, called the princely states, that were ruled by Indian rulers under a system of paramountcy. The Dominion of India was formalised by the passage of the Indian Independence Act 1947, which also formalised an independent Dominion of Pakistan—comprising the regions of British India that are today Pakistan and Bangladesh. The Dominion of India remained "India" in common parlance but was geographically reduced. Under the Act, the British government relinquished all responsibility for administering its former territories. The government also revoked its treaty rights with the rulers of the princely states and advised them to join in a political union with India or Pakistan. Accordingly, the British monarch's regnal title, "Emperor of India," was abandoned.

A dominion was any of several largely self-governing countries of the British Empire. Progressing from colonies, their degrees of colonial self-governance increased unevenly over the late 19th century through the 1930s, and some vestiges of empire lasted in some areas into the late 20th century. With the evolution of the British Empire into the Commonwealth of Nations, finalised in 1949, the dominions became independent states, either as Commonwealth republics or Commonwealth realms.