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 Gregorian year 2019 corresponds to Heisei 31. Korea started using the Gregorian calendar on 1 January 1896, which was the 17th day of the 11th lunar month not only in Korea but also in China, which still used the lunisolar calendar. The lunisolar Korean calendar is now used for very limited unofficial purposes only. The North Korean calendar uses Gregorian months and days, but with Kim Il-Sung's year of birth (1912) used as year 1. The Republic of China government under Provisional President Sun Yat-sen abolished the lunisolar Chinese calendar and adopted the Gregorian calendar on 1 January 1912. The