Subsidiary Alliance was basically a treaty between the British East India Company and the Indian princely states, by virtue of which the Indian kingdoms lost their sovereignty to the English. It also was a major process that led to the building of the British Empire in India. It was framed by Lord Wellesley, the Governor-General of India from 1798 to 1805. It was actually used for the first time by the French Governor-General Marquis Dupleix.
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The Doctrine of Lapse was introduced by Lord Dalhousie. According to this doctrine, if any Indian ruler dies without leaving a male heir, his kingdom would automatically pass over to the British.
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