Chinese calendar by mountain peoples. After Qin Shi Huang unified China under the Qin dynasty in 221 BC, the Qin calendar () was introduced. It followed most of the rules governing the Zhuanxu calendar, but the month order was that of the Xia calendar; the year began with month 10 and ended with month 9, analogous to a Gregorian calendar beginning in October and ending in September. The intercalary month, known as the second "Jiǔyuè" (), was placed at the end of the year. The Qin calendar was used into the Han dynasty. Emperor Wu of Han introduced reforms halfway through his
Lithuanian calendar month names on this artifact are expressed in symbols, based on natural phenomena and agricultural cycles. (i.e. the sidereal month was divided into three parts). The Julian calendar was used in the Grand Duchy of Lithuania; the Gregorian calendar was adopted by the Polish-Lithuanian Commonwealth in 1586, a few years after its promulgation in 1582 by Pope Gregory XIII. In 1800, following Lithuania's annexation by the Russian Empire, the Julian calendar again became the norm, although a part of ethnic Lithuania left of Nemunas River (Suvalkija) retained the Gregorian calendar (see Aleksotas). The Russian Revolution of 1917 re-instated the Gregorian