Calendar of the Black Thai in Vietnam

The Black Thai in Son La province base their calendar on the phases of the moon.

Calendar of the Black Thai in Vietnam

An almanac of the Black Thai

Important events such as funerals, weddings, ground breakings, house-warmings, and crop plantings are organized on lucky days of the lunar month. 

The lunar calendar of the Black Thai is a cultural heritage which has been transferred from generation to generation of Thai shamans for thousands of years.

Thai folklore says their ancestors migrated to the Muong Lo valley in Yen Bai province thousands of years ago. They cultivated the land and expanded their habitat throughout in the northwest region of Vietnam.

Thai shamans brought with them an almanac to help them choose days for important activities.

The Black Thai calendar is based on the 12-zodiac signs but is shifted 6 months compared to the modern solar calendar.

Old almanacs described the weather for each month: in the first and second months, continuos rains; in the third month, water inundates the wharf; in the fourth and fifth months, less rains; in the sixth month, cold and stormy; in the seventh month, cold strong winds and so on.

The old Black Thai consulted the moon and the stars before planting. Experienced people could forecast a season of more or less rain and wind by watching where the ants made their nests.

Lo Van Chung, a researcher of the Black Thai calendar, said, “Ancient Thai people looked at the time certain fruits ripened in the forest to decide when to sow their rice. Villagers asked the shamans to help them select lucky days.”


The Black Thai in Son La, Dien Bien, Lai Chau, and Yen Bai province still use their ancient calendar to schedule traditional ceremonies.

Calendar of the Black Thai in Vietnam
An almanac helps the Black Thai people choose days for important activities.

Ca Van Chung, a Thai man who works for the Department of Science and Technology in Son La province, computerized the Black Thai calendar to facilitate comparisons between the Black Thai calendar and popular solar and lunar calendars.

“The Black Thai calendar is available on the computer. The Vietnam Folklore Association printed 400 years of it in 7 volumns,” Chung said.

The calendar of the Black Thai was built on their experience of comparing the cycles of the moon, plants, and the weather. It’s part of their rich and ancient culture. VOV