The sant movement ran across northern India from roughly the fourteenth century, and its poets were mostly artisans and labourers rather than brahmins. Kabir was a weaver of Varanasi, claimed after his death by Hindus and Muslims alike. Ravidas was a leatherworker whose followers now form a distinct religious community with its own places of worship. Namdev was a Marathi speaker whose compositions entered the Sikh scripture in this idiom rather than in Marathi.
Their common ground was a formless divine reachable without ritual, image or intermediary, an attack on caste and on the professional religiosity of both Hindu and Muslim establishments, and a poetry made to be sung rather than read. W. H. McLeod's work on Sikhism and J. S. Grewal's history of the Sikhs of the Punjab set the Gurus within that wider movement while marking where Sikh teaching departs from it.
Because the poetry circulated orally before it was written down, the same composition survives in several recensions, and attribution is genuinely uncertain for a great deal of what is ascribed to Kabir in particular. The atlas records the corpus as shared and contested rather than assigning every verse to a named author, since the traditions holding it do not agree among themselves about which verses are whose.