'Chuseok' (Chu-Sok), literally "Autumn eve", is a major harvest festival and a three-day holiday in both North & South Korea celebrated on the 15th day of the 8th month of the lunar calendar on the full moon. Like many other harvest festivals around the world, it is held around the autumn equinox at the very end of summer or in early autumn.

Many scholars believe 'Chuseok' may originate from ancient shamanistic celebrations of the harvest moon. New harvests are offered to local deities and ancestors, which means 'Chuseok' may have originated as a worship ritual. In some areas, if there is no harvest, worship rituals are postponed, or in areas with no annual harvest, 'Chuseok' is not celebrated.

'Chuseok' celebrates the bountiful harvest and strives for the next year to be better than the last. People perform ancestral worship rituals early in the morning. Then, they visit the tombs of their immediate ancestors to trim plants and clean the area around the tomb, and offer food, drink, and crops to their ancestors.

Koreans consider autumn the best season of the year due to clear skies, cool winds, and it is a perfect harvesting season. Harvest crops are attributed to the blessing of ancestors.

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