The poster’s question should be about why India can get rid of colonization and gain independence through non-violent means, while many other countries can only gain independence through violence (such as the Chinese revolution).

I think the main reason was that the international environment at that time forced Britain to give up the Indian colony:

1. Colonial independence has become a historical trend;

2. The United Kingdom fell into the quagmire of World War II, and after World War II, its strength was greatly reduced, and it was no longer the "empire on which the sun never sets";

3. The United States and the Soviet Union did not see the United Kingdom still there after World War II. There are such large colonies in Asia;

4. As a colony, India only has the British "sovereign country", and the colonial time is long, but the contradictions are simple (unlike China, in just a hundred years, the various forces have become so different. The other is ebbing and the other is increasing, and the contradiction is more complicated).

In addition, the West admires Gandhi very much, simply because Gandhi’s behavior is more in line with their values.