Showa Day is a Japanese annual holiday held on April 29. Part of Golden Week.
It honours the birthday of Emperor Hirohito, the reigning Emperor before, during, and after World War II (from 1926 - 1989).
Traditionally the Emporer's birthday was a national holiday, and after the death of Emperor Hirohito in January 1989, April 29 was subsequently no longer celebrated as The Emperor's Birthday but instead as Greenery Day, part of Japan's Golden Week.
After many attempts since 2000, Greenery Day finally won approval to be renamed Shōwa Day in May 2005, and the decision to move the date of Greenery Day from April 29 to May 4 was taken.
The official purpose of the holiday is to reflect on Japan's Showa period when the nation recovered after the turbulent times, and to think about the country's future.