The mythology, as well as the cosmogony of the Egyptians, Greeks and Romans, were borrowed from the doctrines of the Brahmins.
Source, in full
John Holwell, quoted in Marshall, P. J. 1970. The British Discovery of Hinduism in the Eighteenth Century. Camhridge: Cambridge University Press. Quoted from Bryant, E. F. (2001). The Quest for the Origins of Vedic Culture : the Indo-Aryan migration debate. Oxford University Press. chapter 1.