In Japanese, the month is known as ichigatsu (Japanese: 一月) or traditionally mutsuki (Japanese: 睦月).
According to the 12th century poet Fujiwara no Kiyosuke, mutsuki is named after the friendly/affectionate (Japanese: 睦まじい, romanized:mutsumajī) gatherings of relatives at the beginning of the year. Alternatively, it may come from もとつ月, meaning the first or original month.
Tết is celebrated on the 1st day of the 1st month in Vietnam.
The Shen Zhu festival is held on the 6th day of the 1st month in Taiwan.
Jinjitsu was traditionally observed on the 7th day of the 1st month in Japan.
Daeboreum is celebrated on the 15th day of the 1st month in Korea.
Yabuiri[ja] (Japanese: 藪入り) was a festival traditionally observed on the 16th day of the 1st and 7th months, on which apprentices, servants and maidservants were given gifts and allowed to return to their parents' homes for the day.
Guan Yu, a general serving under the warlord Liu Bei in the late Eastern Han dynasty, Zhēngyuè 13, 220
Cao Cao, a warlord and the penultimate chancellor of the Eastern Han dynasty who rose to great power in the final years of the dynasty, Zhēngyuè 23, 220
Below is a list of the start and end dates of Zhēngyuè in the Gregorian calendar. Because the 1-hour difference between China and Japan/Korea occasionally affects the date on which a new moon occurs, the dates below can differ from those of the Japanese and Korean calendars.