When it comes to 祝日 (shukujitsu, national holidays) in Japan, you’ll find there’s a bit of a drought in 六月 (roku-gatsu, June). That’s funny because June is also when 梅雨 (tsuyu, rainy season) occurs. Anyway, the closest we get to a holiday in June is 父の日 (chichi no hi, Father’s Day) on the third Sunday of June, which is June 16 this year.
June 16 is historically known as 和菓子の日 (wagashi no hi, Japanese Sweets Day), a designation that dates back to the year 848 when Emperor Ninmyo offered sweets and rice cakes to the gods in exchange for good health. The era of his reign would later be identified by three 元号 (gengō, era names), the latter of which was 嘉祥 (kashō [kajō], Kasho). It lasted from 848 until 851, the year after the emperor’s death in 850.
嘉祥 has come to mean “good omen” or “auspicious sign,” おめでたいしるし (omedetai shirushi) in Japanese, as well as being connected to 和菓子 (wagashi, Japanese confectionery). And when we say 和菓子, we’re not talking about chocolate — think 餅 (mochi, rice cake) and 小豆 (azuki, red beans) served with seasonal 果物 (kudamono, fruit).