You truly need to read some real Indian history. The Mughals and their predecessors won North India by bloody conquest that make the British look like saints. I won't document the extraordinary slaughter during this period. See wikipedia for what Timur did to Delhi (after it surrendered) for example. He proudly describes the slaughter in his autobiography: https://www.ibiblio.org/britishraj/Jackson5/chapter09.html http://cw.routledge.com/textbooks/9780415485432/19.asp

Due to the powerful Vijaynagar empire, South India remained free for some time. At this time, you actually had Queens ruling Kerala (Attingal Queens). When the Vijaynagar empire weakened, the Deccan and Delhi sultanates united and thanks to the betrayal of two Muslim generals was thoroughly defeated in the Battle of Talikota. The massacre and rapine that occurred after defeat is still known to the local historians of the area.

https://en.wikipedia.org/wiki/Battle_of_Talikota

Modern day Kerala was invaded by Haider Ali (Sultan of Mysore) though he faced very stiff resistance. He then decided to slaughter entire civilian populations. Believe it or not, it is thanks to the East India Company who supplied weapons to the Malabar Hindus who made constant guerrilla style attacks from the forests that Haider Ali backed off!

The princely states that comprised Modern Kerala never truly had a problem with the British. Travancore and Kochi were extremely rich and sovereign monarchies who gave their alliance to the Queen, retaining their rule and benefiting from the British in trade.