Gandhi's impact can be seen in at least three ways: (1) through those who were inspired by Gandhi; (2) those who influenced Gandhi (Tolstoy, John Ruskin, etc.,), and notably became icons to be followed by many others, at least in India; and (3) through the iconic relationships that Gandhi forged through his lifelong interactions with people;
Gandhi's iconic relationships spanned the spectrum of those in politics, social reform, education, literature, the sciences, and many others. He was a prolific letter writer and kept in touch with people whether in station or traveling, whether in or out of jail.
The list of those who inspired Gandhi is less known than the list of those who were inspired by Gandhi. Gandhi drew inspiration from a wide range of icons, both international as well as national. Within the Indian subcontinent, this stretched from Bengal in the east to the borders of Afghanistan in the west.
This is an inspired list although quite well-known to all, and continues to grow even as we write.