well indian subcontinent being a home to different nations n groups f people faced many conflicts from within.whenevr a nation is defeated external factors do count but if the attackd society is itself integrated its even harder to conquere it.so no matter this peice f statement is authentic or not,every society possess weakness whereas this sub continent was suffering through numerous dilemmas.e.g indians who faced numerous dynaties ruling over them n one dynasty soon rooted by another,they were tired of centuries old mughal dynasty.of course this is not the only factor f british sucess over indins!

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