In Roman mythology, the god Janus oversaw beginnings and endings, of starting up and winding down, of passage. The month of January was named for him – Mentis Ianuarius, the Month of Janus. Although it should be pointed out that old Roman farmer’s almanacs cite the goddess Juno as the month’s patron. But she was the daughter of Saturn, the wife of Jupiter and protector of Rome and the empire. She was regarded as the queen, or Beyoncé, of the gods. That’s branding for you.
For all the tittering about gladiators and orgies, the ancient Romans were pretty pious people in their own way. Not terribly spiritual in that inward-looking sense, this was a transactional, devotions-on-the-barrelhead style religion. You didn’t have to be your best self, or terribly moral – that wrapped up in social standing. But you damn sure had better light that candle at the temple or sacrifice that gopher becausethey were sticklers about sort of thing.
The gods weren’t all loving but pedantic and vindictive. Like the petty, rancorous and powerful on earth, the gods liked to have their names slapped on buildings and streets and bridges. In a mostly illiterate world this was done with imagery, and Janus was always depicted as having two faces, not out of hypocrisy, but one face looking to the past, and the other to the future. In fact, Janus didn’t have temples erected in his honor, but managed to have his mug - both of them - planted on nearly every gate and doorway of note in the eternal city.
The patrons of the harvest, the hunt or even war, could be contained in a temple waiting for rites to be performed for contained functions. Change, as overseen by Janus, was everywhere, always moving from past to the future. Mars may have been the God of War, but it was Janus who oversaw both war and peace because the end of one is necessarily the beginning of the other. The ancients knew that change was a constant, that all things must end and that death is the start of something else.