Korean calendar

Throughout its many years of history, various calendar systems have been used in Korea. Many of them were adopted from the lunar Chinese calendar system, with modifications occasionally made to accommodate Korea's geographic location and seasonal patterns.
The solar Gregorian calendar was adopted in 1896, by Gojong of Korea. Koreans now mostly use the Gregorian calendar; however, traditional holidays and age-reckoning for older generations are still based on the traditional lunisolar calendar.

History

During the early Goryeo period, the Tang-made Xuanming calendar was used until 1281. While the Tang revised the Xuanming calendar several times, Korea insisted on using an unmodified version until Munjong's reign, when several improvised calendars were created, such as the Sipchŏng, Ch'iryo, Kyŏnhaeng, Tun'gap, and T'aeil calendars.
In 1281 the Yuan-made Shòushí calendar 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, saw limited use.
Shòushí continued as the standard calendar until early Joseon, when the Ch'ilchŏngsan was created to serve as the first Korea-specific calendar system during the reign of Sejong the Great. The Ch'ilchŏngsan consisted of two books, the Ch'ilchŏngsannaep'yŏn, which detailed methods to accurately calculate dates and celestial movements regarding Korea's geographic location based on the Shòushí calendar, and the Ch'ilchŏngsanoep'yŏn, which was based on the Huihui Lifa.
Beginning in 1644, Korean scholars began discussing the adaptation of the Qing-made Shixian calendar, as the limitations of the Ch'ilchŏngsan became clear. Although the Shixian calendar was officially adopted in 1653, it was not implemented in earnest until 1725 as Korean scholars had little knowledge of western astronomy and the Qing were reluctant to reveal any information of their new innovation.
The traditional calendar designated its years via Korean era names from 270 to 963, then Chinese era names with 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 the Joseon Dynasty in 1392.
The Gregorian calendar was adopted on 1 January 1896, with the Korean era name Geonyang.
File:최준례, 김구 부인의 무덤.png|thumb|The gravestone of Kim Ku's wife, Ch'oe Chun-rye, uses the Dangun calendar written using hangul numerals for her birth year. For her death year, it uses hangul numerals to indicate the number of years after the founding of the Korean Provisional Government.|262x262px
From 1945 until 1961 in South Korea, the Dangun calendar was used, where Gregorian calendar years were counted from the foundation of Gojoseon in 2333 BC, the date of the legendary founding of Korea by Dangun. These Dangi 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 the Shixian calendar, which was in turn revised by Jesuit scholars.
In North Korea, the Juche calendar was used between 1997 and 2024 to number its years, based on the birth of the state's founder Kim Il Sung.

Features

The Chinese zodiac of 12 Earthly Branches, which were used for counting hours and years;
Ten Heavenly Stems, which were combined with the 12 Earthly Branches to form a sixty-year cycle;
Twenty-four solar terms in the year, spaced roughly 15 days apart;
Lunar months including leap months added every two or three years.
Weekdays

Note that traditional Korean calendar has no concept of weekdays: the following are names of weekdays in the modern calendar.

English	Hangul	Hanja	Transliteration	Heavenly body	5 Elements
Sunday		日曜日	:	Sun
Monday		月曜日	:	Moon
Tuesday		火曜日	:	Mars	Fire
Wednesday		水曜日	:	Mercury	Water
Thursday		木曜日	:	Jupiter	Wood
Friday		金曜日	:	Venus	Metal
Saturday		土曜日	:	Saturn	Earth

Months

In modern Korean language, the months of both the traditional lunisolar and Western calendars are named by prefixing Sino-Korean numerals to, the Sino-Korean word for "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 each Earthly Branch in the Chinese zodiac to, 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 as Xìngyuè for the second month, are not used in Korean.

Festivals

The lunar calendar is used for the observation of traditional festivals, such as Seollal, Chuseok, and Buddha's Birthday. It is also used for jesa memorial services for ancestors and the marking of birthdays by older Koreans.

Traditional holidays

Festival	Significance	Events	Date	Food
Seollal	Lunar New Year's Day	An ancestral service is offered before the grave of the ancestors, New Year's greetings are exchanged with family, relatives and neighbors; bows to elders, yut nori.	Day 1 of Month 1	rice cake soup, honey cakes.
Daeboreum	First full moon	Greeting of the moon, kite-flying, burning talismans to ward off evil spirits, bonfires.	Day 15 of Month 1	rice boiled with five grains, eating nuts, e.g. walnuts, pine nuts, peanuts, chestnuts, wine drinking
Meoseumnal	Festival for servants	Housecleaning, coming of age ceremony, fishermen's shaman rite	Day 1 of Month 2	stuffed pine-flavored rice cakes
Samjinnal	Migrant swallows return	Leg fighting, fortune telling.	Day 3 of Month 3	azalea wine, azalea rice cake
Hansik/ Hanshik	Beginning of farming season	Visit to ancestral grave for offering rite, and cleaning and maintenance.	Day 105 after winter solstice	cold food only: mugwort cake, mugwort dumplings, mugwort soup
Chopail (Cho-pa-il) or Seok-ga Tan-shin-il	Buddha's Birthday	Yeondeunghoe	Day 8 of Month 4	rice cake, flower rice cake
Dano or Surit-nal	Spring festival	Washing hair with iris water, wrestling, swinging, giving fans as gifts	Day 5 of Month 5	rice cake with herbs, herring soup
Yudu	Water greeting	Water greeting, washing hair to wash away bad luck	Day 15 of Month 6	Five coloured noodles, cooked rice cake
Chilseok	Meeting day of Gyeonwu and Jiknyeo, in Korean folk tale	Fabric weaving	Day 7 of Month 7	wheat pancake, steamed rice cake with red beans
Baekjung	Worship to Buddha	Worship to Buddha.	Day 15 of Month 7	mixed rice cake
Chuseok	Harvest festival	Visit to ancestral grave, ssireum, offering earliest rice grain, circle dance	Day 15 of Month 8	pine-flavored rice cake stuffed with chestnuts, sesame or beans, taro soup
Jungyangjeol	Migrant sparrows leave	Celebrating autumn with poetry and painting, composing poetry, enjoying nature	Day 9 of Month 9	chrysanthemum pancake, fish roe, honey citron tea
Dongji	Winter Solstice	Rites to dispel bad spirits.	Around December 22 in the solar calendar	red bean porridge with rice dumplings
Seot-dal Geum-eum	New Year's Eve	Staying up all night long with all doors open to receive ancestral spirits	Last day of Month 12	mixed rice with vegetables, bean powder rice cakes, traditional biscuits

There are also many regional festivals celebrated according to the lunar calendar.