Its founder was Shatakopa, bom in a Kanjar(low caste) family. Later, Munibanan, a bom sweeper, and then Yavanacharya, a Greek or a Muslim, taught it.
It was known as the Bhagwat faith. It also became known as Pancaratra.* It was monotheism and it taught that salvation is the result of Bhakti or devotion. Later, this Bhagwat religion became transformed into Vaishnavism. Its first teacher of note was Yavanacharya later called Yamunacharya. Another teacher Kathu Muni preceded Yavanacharya. The later was a disciple of the Alvars of the Deccan. He arranged their hymns. Yavanacharya defended the Vaishnava faith against attacks upon it and wrote several books.
Is there any evidence to support his claim?