Euhemerism

In regard to the Thracian god Zalmosis, the Hellespontic Greeks interpreted his character and attributes according to the scheme of Euemerism.

Source: wiktionary

Then again there was a period of what is sometimes called Euhemerism - the theory that the gods and goddesses had actually once been men and women, historical characters round whom a halo of romance and remoteness had gathered.

Source: wiktionary

Already before euhemerism saved them by embalming them, [...] they had become in their very being the enlarged shadows of great men and warriors upon the walls of the world.

Source: wiktionary