October (Roman month) October (Roman month) October (from Latin "octo", "eight") or mensis October was the eighth of ten months on the oldest Roman calendar. It had 31 days. October followed September (from "septem", "seven") and preceded November ("novem", "nine"). After the calendar reform that resulted in a 12-month year, October became the tenth month, but retained its numerical name, as did the other months from September through December. Some of the observances in October marked the close of the season for military campaigning and farming, which commenced in March ("Martius", "Mars' month"). October was under the guardianship "(tutela)" of Mars. The Romans
December (Roman month) "(VII Kal. Ian." on the pre-Julian calendar, when December had only 29 days). On the calendar of the Roman Republic and early Principate, each day was marked with a letter to denote its religiously lawful status. By the late 2nd century AD, extant calendars no longer show days marked with these letters, probably in part as a result of calendar reforms undertaken by Marcus Aurelius. Days were also marked with nundinal letters in cycles of "A B C D E F G H", to mark the "market week" December (Roman month) December (from Latin "decem", "ten") or mensis December was