Why was Indian National Army formed?

Is it true that the SCs actually formed the British Indian army which helped them conquer India?

• British Rule in India owes its very existence to the help rendered by the Untouchables. Many Britishers think that India was conquered by the Clives, Hastings, Cootes and so on. Nothing can be a greater mistake. India was conquered by an army of Indians and the Indians who formed the army were all Untouchables. British Rule in India would have been impossible if the Untouchables had not helped the British to conquer India. Take the Battle of Plassey which laid the beginning of British Rule or the Battle of Kirkee which completed the conquest of India. In both these fateful battles the soldiers who fought for the British were all Untouchables. http://www.deeshaa.org/2014/04/12/who-killed-indians-at-jallianwala-bagh/

• Answer:

  Yes. Compared to social tyranny of upper castes they preferred British. But British disbanded these regiments after 1857.    "India was conquered by the British with the help of an Army composed of Indians. It is well for Indians as well as for the British not to overlook this fact. But who were these Indians who joined the army of their foreigners ? That question Prof. Seely did not raise. But it is a very pertinent question. Who were these people who joined the army of the East India Company and helped the British to conquer India ? The answer that I can give—and it is based on a good deal of study— is that the people who joined the Army of the East India Company were the Untouchables of India. The men who fought with Clive in the battle of Plassey were the Dusads, and the Dusads are Untouchables. The men who fought in the battle of Koregaon were the Mahars, and the Mahars are Untouchables. Thus in the first battle and the last battle it was the Untouchables who fought on the side of the British and helped them to conquer India. There are many who look upon this conduct of the Untouchables in joining the British as an act of gross treason. Treason or no treason, this act of the Untouchables was quite natural. History abounds with illustrations showing how one section of people in a Country have shown sympathy with an invader, in the hope that the new comer will release them from the oppressions of their countrymen. Was the attitude of the Untouchables in any way singular ? After all, the tyranny under which the English Labourer lived was nothing as compared with the tyranny under which the Untouchables lived and if the English workmen had one ground to welcome a foreign invader the Untouchable had one hundred." BR Ambedkar.