Coming of Age Day is a Japanese holiday held annually on the second Monday of January. It is held in order to congratulate and encourage all those who have reached the age of majority (20 years old) over the past year, and to help them realize that they have become adults. Festivities include coming of age ceremonies held at local and prefectural offices, as well as after-parties among family and friends.
Coming of age ceremonies have been celebrated in Japan since at least 714 AD, when a young prince donned new robes and a hairstyle to mark his passage into adulthood. The holiday was first established in 1948, to be held every year on January 15. In 2000, as a result of the Happy Monday System, Coming of Age Day was changed to the second Monday in January.
Until recently, all young adults attending the coming of age ceremony were exactly 20, having held their 20th birthday after the previous year’s Coming of Age Day but before (or on) the present Coming of Age Day.