When Ovid reached the fifth month in the Fasti he did something unusual for a poet explaining a calendar: he set out three derivations for the name Maius and refused to pick one. The month might belong to Maiestas, divine majesty; it might belong to Maia, mother of Mercury by Jupiter, whose sacrifice fell on the first of May; or it might honour the maiores, the elders of the community, with the following month answering it for the iuniores, the young. Each account had its advocates in his day, and modern scholarship has not closed the question either, so May stands beside April and June among the Roman spring months whose names were already contested when the poets set out to explain them.
Roman May had a shadowed side. The Lemuria, kept on the ninth, eleventh and thirteenth, was the season when the restless dead walked, and the head of a household rose at midnight to cast black beans over his shoulder nine times, buying the ghosts out of the house. On the fourteenth or fifteenth the pontiffs and Vestals threw rush figures called Argei from the Sacred Bridge into the Tiber, a rite whose meaning was already obscure to the Romans who performed it. Between the ghosts and the cleansing of the temple of Vesta that followed in June, the stretch of late May and early June was held unlucky for marriage, a superstition Ovid records and one that outlived the religion that made it.
The Bona Dea rites of the first of May, closed entirely to men, opened the month with a secrecy that later made them a byword.