The Passage of Time
The eve of the Year of the Snake has lead me to ponder the lunisolar passage of time. An exploration into Vietnam’s Lunar New Year (TET) reveals a fascinating cultural history of timekeeping.
Vietnam, as with many Asian countries, marks time using simultaneous calendars. Whilst the Gregorian calendar is the official timepiece, important aspects informing social life are set by the lunisolar system, which is based on movements of the sun, earth and moon.
Most published calendars in Vietnam have a second, smaller number printed on each day of the official calendar. These discrete numbers are the lunisolar dates and national holidays are fixed by solar dates.
The lunisolar calendar originated in China over 4,000 years ago and was originally set by royalty. However, since winning their independence from the Chinese in the 10th century, Vietnamese kings set their own calendar with each dynasty establishing an imperial calendar office. The French introduced the Gregorian calendar in early 19th century and both calendars were used simultaneously. The Royal Court in Hue would issue the lunisolar calendar and government published the official Gregorian calendar.
The new Vietnamese state of 1954 heralded revised timekeeping by establishing the Gregorian calendar as the sole official administrative calendar. Today, however the lunisolar continues to determine important festival dates, the lunar new year and brings a certain order to social life. The system is linked to divination and horoscopes and forms the basis for many cultural traditions, from wedding ceremonies, building houses and business decisions down to the mundane tasks such as when to cut your hair or when not to eat pork.
Time and the keeping of its passage influences many rich cultural festivities across Asia, in Vietnam the most important festival dates are ~
- TET (Lunar New Year)
- Festival of Hungry Ghosts (15th day of 7th lunar month)
- Mid-Autumn Festival (15th day of 8th lunar month)

