Izumo Zenzai Day

What Is Izumo Zenzai Day?

October 31st is "Izumo Zenzai Day" in Japan. It was established in 2007 by the Izumo Zenzai Society, whose office is in the Izumo Tourism Association in Izumo, Shimane Prefecture, and is certified and registered by the Japan Anniversary Association.

Reading "1031" as "One Thousand Thirty-One"

The date comes from Japanese wordplay: "1031" is treated as "one thousand thirty-one," and the sounds for thousand (sen), three (san), and one (ichi) are read as "zen-za-i." It is an unusual reading, but it makes sense once you know Izumo's deep ties to zenzai.

• Established by: the Izumo Zenzai Society (office: Izumo Tourism Association)
• Year established: 2007
• Wordplay: 1031 = one thousand thirty-one = "zen-za-i"
• What zenzai is: mainly azuki beans simmered sweet with sugar, often served with mochi, shiratama dumplings, or candied chestnuts

Did Zenzai Originate from Izumo's "Jinzai Mochi"?

In the Izumo region, the gods of Japan are said to gather in the 10th month of the old calendar, and a ritual called Kamiari-sai is held. The mochi served then was called "jinzai mochi." One theory holds that "jinzai" shifted in the Izumo dialect to "zunzai" and then "zenzai," and was passed on to Kyoto. While the rest of Japan calls this month "Kannazuki" (the month without gods), in Izumo it is famously called "Kamiarizuki" (the month with gods).

Tips for Marking This Day

• Enjoy zenzai or oshiruko as a snack
• Learn about Izumo's "month with gods" and the Kamiari-sai ritual
• Pair your Halloween sweets with a traditional Japanese treat
• Compare regional differences in azuki-based Japanese sweets

A Warm Sweet Once Served to the Gods

As the air turns chilly in late October, warm zenzai tastes especially good. On October 31st, enjoy a comforting bowl while thinking about Izumo's myths and history.