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1931 is one of the most important dates in the later British Empire. It is the year of the Statute of Westminster, the constitutional instrument by which the self-governing dominions were given legislative independence from the British.
Under the 1865 Colonial Laws Validity Act the British had the power to veto laws produced by colonial governments. The 1865 act also gave the British power to automatically include colonies in its foreign policy decisions, including declarations of war.
The 1926 imperial conference refined the status of the white colonies, giving them equal status with Britain in the British Commonwealth of Nations. The 1931 Statute of Westminster confirmed what was meant by the dominion status of Australia, Canada, the Irish Free State, Newfoundland, New Zealand and South Africa.
India, was excluded because there was an active independence movement, because she shunned dominion status and because Britain had a different relationship with India than she did with the rest of the empire.
One third of the British army was garrisoned in India and paid for by India. That wasn't the case in any other colony. And although the British Crown had run India since 1858, there were few commercial concessions to India.
So from military and economic points alone the British did not want to devolve real power to the Indians. Some in India would have settled for dominion status. Others wanted nothing less than independence.
Collectively they pointed to a declaration made by Lloyd George's India Secretary Edwin Montagu in 1917 that semantically was as debateable as Balfour's Declaration (also in 1917) on a Jewish Homeland.
The key Montagu passage was: "The policy of His Majesty's Government, with which the Government of India are in complete accord, is that of the increasing association of Indians in every branch of the administration and the gradual development of self-governing institutions with a view to the progressive realisation of responsible government in India."
Edwin Montagu, the Secretary of State for India, in 1917 (Getty Images) View more images
Edwin Montagu, 1879-1924
Edwin Montagu was a sickly child and never shone academically, neither at London nor Cambridge (where he was MP from 1906 until 1922). Montagu, after an affair with her, was married to Venetia Stanley, sometime mistress of HH Asquith.
In 1917 he became India Secretary and in that year made his declaration that the goal of British policy in India was to be the "progressive realization of responsible government." Montagu's political end came in 1922 when without Cabinet consent he published the Indian Government's objection to the Treaty of S猫vres that defined the treatment of Turkey after the break-up of the Ottoman Empire.
That even the most popular of viceroys Lord Irwin was forced, in 1929, to tell the expectant Indians that having a goal of self-government didn't mean it would be reached. The declaration of a goal, he said, was only "an assurance of direction". Many Indians thought this an example of British political and constitutional double-dealing.
Lloyd George's India Secretary, Edwin Montagu, stated in August 1917 :
"The policy of His Majesty's Government, with which the Government of India are in complete accord, is that of the increasing association of Indians in every branch of the administration and the gradual development of self-governing institutions, with a view to the progressive realisation of responsible government in India as an integral part of the British Empire. I would add that progress in this policy can only be achieved by successive stages. The British government and the government of India, on whom the responsibility lies for the welfare and advancement of the Indian peoples, must be the judges of the time and measure of each advance, and they must be guided by the co-operation received from those upon whom new opportunities of service will thus be conferred and by the extent to which it is found that confidence can be reposed in their sense of responsibility."