The Equirria were said to have been founded by
Romulus, the son of Mars. Both appear on the oldest
Roman calendars inscribed on stone. The Equirria are part of what Michael Lipka calls "temporal focalization" in the Roman conception of deity. The festivals of Mars—the 27 February Equirria, a
feria on the
Kalends of March (a day sacred also to
his mother Juno),
Agonalia 17 March,
Tubilustrium 23 March, the ritual of the
October Horse 15 October, and
Armilustrium 19 October—cluster at his namesake month (Latin
Martius), except for festivals of Mars in October to close the
military campaigning season. In the earliest form of the calendar, the year began with March, and thus the 27 February Equirria originally preceded
New Year's Day, and was the last festival for Mars of the year. The 14 March Equirria occurs the day before the
Ides, when the Roman people celebrated the feast of
Anna Perenna, whose name expresses her role as a goddess of the year (Latin
annus; cf. English "perennial"). The March Equirria and the
Regifugium ("King's Flight") are the only such festivals to fall on an even-numbered date. Despite scholarly efforts, no explanation for this displacement has found wide acceptance.
Georg Wissowa thought the March Equirria had originally occurred on the Ides, and was moved up a day because of conflicts among religious events concentrated around this ritually fraught time; an alternate view is that it was placed "at some convenient day" between the
Nones and the Ides. At any rate, the horse races framed the ritual turn of the year, and the difficulties of the placement of the two Equirria arise from changes made to the calendar, when January became the first month. ==Significance==