Rani Lakshmibai or Jhansi Ki Rani opposed to the East India Company because they had created the Doctrine of Lapse. According to the Lapse, a female heir or adopted son could not takeover the kingdom after the death of the king. Only if the king was blessed with a son to rule after him, the kingdom would be left untouched. or else, the British would take over the kingdom. Such happened with Rani Lakshmibai. She got angry at the British not letting her rule Jhansi. 
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