Swami Ramananda proved to be a very strong and successful medium of Bhakti in the second-half of 14th century.
He preached in regional languages. This opened the door of Vaishnav Bhakti for localites.
Ramananda adopted preachings of past gurus, added his own words and then preached the people. By doing so, he inspired the Bhakti revolution in north India.
Kabir and Raidas were among his several followers.