In the year 1966, Srila Prabhupada began a practice of chanting the Hare Krishna mahamantra every afternoon under a tree in New York's Tompkins Square Park as a means of introducing Americans to the great chant of deliverance. This launched Lord Caitanya Mahaprabhu's glorious Sankirtana movement in the western world from where it would envelop the globe.
Krishna is within your heart. If you kindly continue to hear about Him, as you are doing, then Krishna will be very much pleased, "Oh, this person is now interested in me." Because nobody's interested in Krishna, so Krishna is also silent to them. But as soon as you become interested, oh Krishna becomes very active, "Oh, he's trying to do something. I shall help him." - Srila Prabhupada (Los Angeles, May 19, 1972)
In 1967, Srila Prabhupada introduced the youth of America to the 'Hare Krishna Mantra' by holding Sankirtana at the Golden Gate Park in San Francisco. They were greatly attracted to the Sankirtana and some of them later became his disciples.