CC Adi 10.53 purport:

In 1434 Sakabda (A.D. 1512), when Lord Nityananda Prabhu was empowered by Lord Caitanya to preach the sankirtana movement in Bengal, Sri Gadadhara dasa was one of Lord Nityananda’s chief assistants. He preached the sankirtana movement by requesting everyone to chant the Hare Krsna maha-mantra. This simple preaching method of Srila Gadadhara dasa can be followed by anyone and everyone in any position of society. One must simply be a sincere and serious servant of Nityananda Prabhu and preach this cult door to door.