When I first came across the term Bhakti Movement in school, I assumed that it was a typical social movement in which selected spiritual leaders across India who shared a common objective planned and propagated some social reforms. Today, I believe that this occurrence in late medieval India, when Hindu spirituality was at its lowest due to political reasons and ethical confusion, was one of its own kind.
Because bhakti (true love of God) can never be induced in members of a group by active participation but has to be granted by the Divine, we cannot assert that the Bhakti Saints had a common goal* when they started out in their life. Saints like Mirabai, Tulasidasa, and Surdasa did not have any plans for worshipping God; they just fell in love with him due to their individual spiritual experiences. While there were interactions and possible exchanges of teachings between a few Bhakti Saints in later life, the reform of the Indian society that the bhakti phenomenon caused was not pre-planned. Spiritual rise of many individuals, improvements for the so-called lower castes, and release of spirituality from the grip of the intelligentsia were simple side effects of the individual spiritual rise of these saints. When the Bhakti Saints met God, they started spreading his message of oneness among beings. However, the timing of their presence in different parts of the Indian subcontinent was so perfect that it gave the results of a harmonized social movement across India and changed Hindu thought forever.
Can human beings design such a perfect phenomenon which spans over centuries but still reflects a concurrence of its constituent events in times of great need? I doubt it. This upliftment of people by positive vibrations from the enlightened seems to be organized by God himself.
*Pure bhakti cannot nurture in the presence of any objectives in the mind.