Question

how did the subsidiary alliance and doctrine of lapse help the British to gain control over India

Answer 1

SUBSIDIARY ALLIANCE=it was introduced by lord wellesly according to this if a ruler accept subsidiary alliance then he had to take care of force of British he had to pay tax and british protect them from invader.so ruler accept the subsidiary alliance.

DOCTRINE OF LAPSE= it was introduced by lord dalhousie according to this if a ruler died without a male heir then his kingdom was lapsed so this also helped british empire to capture india.