September (Roman month) September (Roman month) September (from Latin "septem", "seven") or mensis September was originally the seventh of ten months on the ancient Roman calendar that began with March ("mensis Martius", "Mars' month"). It had 29 days. After the reforms that resulted in a 12-month year, September became the ninth month, but retained its name. September followed what was originally Sextilis, the "sixth" month, renamed "Augustus" in honor of the first Roman emperor, and preceded October, the "eighth" month that like September retained its numerical name contrary to its position on the calendar. A day was added to September in the mid-40s
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