November (Roman month) November (Roman month) November (from Latin "novem", "nine") or mensis November was originally the ninth of ten months on the Roman calendar, following October ("octo", "eight") and preceding December ("decem", "ten"). It had 29 days. In the reform that resulted in a 12-month year, November became the eleventh month, but retained its name, as did the other months from September through December. A day was added to November during the Julian calendar reform in the mid-40s BC. The outstanding event during November was the Plebeian Games from the 4th through the 17th. The month had few other festivals. It was
Adoption of the Gregorian calendar the old style calendars were similar but not all the same. The Arabic numerals may be used for both calendar dates in modern Japanese and Korean languages, but not for Chinese old-style dates. Japan started using the Gregorian calendar on 1 January 1873, locally known as . The preceding day, 31 December 1872, was . Japan currently uses two eras: the western era and a modified traditional Japanese era name (nengō). The months and days are those of the Gregorian calendar, but the year is either the western year number or a year of the nengō of the emperor on