What conditions gave rise to India's decolonization?
India, once the jewel of the British empire, had by the twentieth century become less profitable and more expensive to manage than it had once been. It's important to note that during the first part of the twentieth century, England had been hammered by two worlds wars that exhausted it financially. World War II was especially hard on Britain. By the end of the war, the country had to acknowledge that it no longer would be, as it had been for more than a century, the world's preeminent superpower. It passed that baton to the United States and began to pull back from the world stage.
By the mid-20th century, classic colonialism had become expensive and outdated as a way of extracting wealth from other countries, but factors other than the financial prodded England to free India. First, having embraced a rhetoric of freedom and democracy in the fight against Hitler and the Nazis, the English found it more and more intellectually difficult to justify ruling India: old notions of the "white man's burden" and white racial superiority had become embarrassing and were increasingly challenged. Finally, British betrayals of various Indian groups had united formerly rival territories in India into one whole, with the shared goal of ridding the country of their foreign ruler. This, along with Gandhi's galvanizing work to free India, let to an upsurge of Indian nationalism that added to the English impetus to get rid of colony that was becoming more trouble than it was worth.