How did Kashmir end up largely under Indian control?

Nestling at the point where the borders of India and Pakistan meet in the Himalayas, Jammu and Kashmir is the only Muslim-majority state or territory in Hindu-majority India (excepting the tiny Lakshadweep archipelago). It has been a flashpoint between India and Pakistan since Partition in 1947, partly because of its geo-strategic importance.

The glacial waters flowing through Kashmir provide water and electricity to tens of millions of people in India; Pakistan's biggest river, the Indus, also passes through it.