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
Adoption of the Gregorian calendar to use their own calendars, which usually result in fixed dates being celebrated in accordance with the Julian calendar. This is most interesting in the case of the Syriac Orthodox Church, as one of its Patriarchs Ignatius Nemet Allah I was one of the nine scholars who devised the Gregorian calendar. The Indian Orthodox Church uses the Gregorian calendar along with their autonomous Syriac Orthodox counterparts in India, the Malankara Jacobite Syriac Orthodox Church. The Armenian Apostolic Church adopted the Gregorian calendar in 1923, except in the Armenian Patriarchate of Jerusalem, where the old Julian calendar is still in use.