National Foundation Day or Kenkoku Kinen no Hi is celebrated on February 11, 2021 in Japan. It is a Japanese national holiday to celebrate the founding of the nation. However there are no huge festivities on National Foundation Day, taking part rather means to wave some Japanese flags and mute thoughts about Japan and what it means to live there and patriotically love the country.
Emperor Jimmu, the first Emperor of Japan, got coroneted on the first day of the first month of the Iunisolar calendar. In 1873 this date had been transformed into the Gregorian calendar. The day was firstly known as Lunar New Year, then Empire Day and since 1966 is celebrated as National Foundation Day. So this day is about the beginning of Japan, meaning the accession of Jimmu and the Japanese Constitution of 1946.