Korean calendar

Throughout its many years of history, various calendar systems have been used inKorea. Many of them were adopted from thelunarChinese calendarsystem,with modifications occasionally made to accommodate Korea's geographic location and seasonal patterns.
The solar Gregorian calendar was adopted in 1896, byGojong of Korea.Koreans now mostly use theGregorian calendar; however, traditional holidays andage-reckoningfor older generations are still based on the traditionallunisolar calendar.
During the earlyGoryeoperiod, the Tang-madeXuanmingcalendar(선명력; 宣明曆) was used until 1281.While the Tang revised the Xuanming calendar several times Korea insisted on using an unmodified version untilMunjong's reign, when several improvised calendars, such as theSipchŏng(십정력; 十精曆),Ch'iryo(칠요력; 七曜曆),Kyŏnhaeng(견행력; 見行曆),Tun'gap(둔갑력; 遁甲曆), andT'aeil(태일력; 太一曆) calendars were created.
In 1281 (the 7th year ofChungnyeol's reign) the Yuan-madeShòushícalendar(수시력; 授時曆) was adopted.However, Goryeo scholars tended to prefer the obsolete Xuanming calendar, which they were more accustomed to. During the late Goryeo period a revised version of Shòushí, known as the Taet'ong calendar (대통력; 大統曆) saw limited use.
Shòushí continued as the standard calendar until early Joseon when theCh'ilchŏngsan(칠정산; 七政算) was created to serve as the first Korea-specialized calendar system during the reign ofSejong the Great. The Ch'ilchŏngsan consisted of two books, theCh'ilchŏngsannaep'yŏn(칠정산내편; 七政算內篇) which detailed methods to accurately calculate dates and celestial movements regarding Korea's geographic location based on the Shòushí calendar, and theCh'ilchŏngsanoep'yŏn(칠정산외편;七政算
外篇), which was based on theHuihui Lifa.
Beginning in 1644 (22nd year ofInjo's reign), Korean scholars began discussing the adaptation of the Qing-madeShixian calendar(시헌력;時憲暦;siheollyeok), as the limitations of the Ch'ilchŏngsan became clear. Although the Shixian calendar was officially adopted in 1653 (4th year ofHyojong's reign), it was not implemented in earnest until 1725 (1st year ofYeongjo's reign) as Korean scholars had little knowledge of western astronomy (which heavily influenced the Shixian calendar) and the Qing were reluctant to reveal any information of their new innovation.
The traditional calendar designated its years viaKorean era namesfrom 270 to 963, thenChinese era nameswith Korean era names at a few times until 1894.In 1894 and 1895, the lunar calendar was used with years numbered from the foundation of theJoseonDynasty in 1392.
The Gregorian calendar was adopted on 1 January 1896,with theKorean era nameGeonyang (건양;建陽;lit.'adopting solar calendar').
From 1945 until 1961 inSouth Korea, theDangun calendarwas used, where Gregorian calendar years were counted from the foundation ofGojoseonin 2333BC(regarded as year one), the date of the legendary founding of Korea byDangun.These Dangi (단기;檀紀) years were 4278 to 4294. This numbering was informally used with the Korean lunar calendar before 1945 but has only been occasionally used since 1961, and mostly in North Korea prior to 1997.
Although not being an official calendar, in South Korea, the traditional Korean calendar is still maintained by the government. The current version is based on theShixian calendar, which was in turn revised by Jesuit scholars.
InNorth Korea, theJuche calendarwas used between 1997 and 2024 to number its years, based on the birth of the state's founderKim Il Sung.
Note that traditional Korean calendar has no concept of weekdays: the following are names of weekdays in the modern (Western) calendar.
In modern Korean language, the months of both the traditional lunisolar and Western calendars are named by prefixingSino-Korean numeralstowol, theSino-Korean wordfor "month". Traditionally, when speaking of individuals' birth months, the months of the lunisolar calendar were named by prefixing the native Korean name of the animal associated with eachEarthly Branchin theChinese zodiactodal, the native Korean word for "month". Additionally, the first, eleventh, and twelfth months have other Korean names which are similar to traditional Chinese month names.However, the other traditional Chinese month names, such asXìngyuè("apricot month") for the second month, are not used in Korean.
The lunar calendar is used for the observation of traditional festivals, such asSeollal,Chuseok, andBuddha's Birthday. It is also used forjesamemorial services for ancestors and the marking of birthdays by older Koreans.
There are also many regional festivals celebrated according to the lunar calendar.