J.G. Frazer in the context of "Fasti (Ovid)"

The Fasti (Latin: Fāstī [ˈfaːstiː], "the Calendar"), sometimes translated as The Book of Days or On the Roman Calendar, is a six-book Latin poem written by the Roman poet Ovid and made public in AD 8. Ovid is believed to have left the Fasti incomplete when he was exiled to Tomis by the emperor Augustus in 8 AD. Written in elegiac couplets and drawing on conventions of Greek and Latin didactic poetry, the Fasti is structured as a series of eye-witness reports and interviews by the first-person vates ("poet-prophet" or "bard") with Roman deities, who explain the origins of Roman holidays and associated customs—often with multiple aetiologies. The poem is a significant, and in some cases unique, source of fact in studies of religion in ancient Rome; and the influential anthropologist and ritualist J.G. Frazer translated and annotated the work for the Loeb Classical Library series. Each book covers one month, January through June, of the Roman calendar, and was written several years after Julius Caesar replaced the old system of Roman time-keeping with what would come to be known as the Julian calendar.

The popularity and reputation of the Fasti has fluctuated more than that of any of Ovid's other works. The poem was widely read in the 15th–18th centuries, and influenced a number of mythological paintings in the tradition of Western art. However, as scholar Carole E. Newlands has observed, throughout the 20th century "anthropologists and students of Roman religion … found it full of errors, an inadequate and unreliable source for Roman cultic practice and belief. Literary critics have generally regarded the Fasti as an artistic failure." In the late 1980s, however, the poem enjoyed a revival of scholarly interest and a subsequent reappraisal; it is now regarded as one of Ovid's major works, and has been published in several new English translations. Ovid was exiled from Rome for his subversive treatment of Augustus, yet the Fasti continues this treatment—which has led to the emergence of an argument in academia for treating the Fasti as a politically weighted work.

A vegetation deity is a nature deity whose disappearance and reappearance, or life, death and rebirth, embodies the growth cycle of plants. In nature worship, the deity can be a god or goddess with the ability to regenerate itself. A vegetation deity is often a fertility deity. The deity typically undergoes dismemberment (see sparagmos), scattering, and reintegration, as narrated in a myth or reenacted by a religious ritual. The cyclical pattern is given theological significance on themes such as immortality, resurrection, and reincarnation. Vegetation myths have structural resemblances to certain creation myths in which parts of a primordial being's body generate aspects of the cosmos, such as the Norse myth of Ymir.

In mythography of the 19th and early 20th century, as for example in The Golden Bough of J.G. Frazer, the figure is related to the "corn spirit", "corn" in this sense meaning grain in general. That triviality is giving the concept its tendency to turn into a meaningless generality, as Walter Friedrich Otto remarked of trying to use a "name as futile and yet pretentious as 'Vegetation deity'".