 According to Dandekar, what is understood today as Vaishnavism did not originate in Vedism at all, but emerged from the merger of several popular theistic traditions which developed after the decline of Vedism at the end of the Vedic period, closely before the second urbanisation of northern India, in the 7th to 4th century BCE.It initially formed around Vāsudeva, a deified leader of the Vrishnis, and one of the Vrishni heroes.Later, Vāsudeva was amalgamated with Krishna "the deified tribal hero and religious leader of the Yadavas", to form the merged deity "Bhagavan Vāsudeva-Krishna", due to the close relation between the tribes of the Vrishnis and the Yadavas.