Which Fukuoka confectioner marketed marshmallows to men before White Day?

The Fukuoka confectioner that marketed marshmallows to men before White Day was Ishimura Manseido.

In 1977, this Fukuoka-based confectionery company promoted marshmallows as a response gift for men to give on March 14. The campaign called the occasion “Marshmallow Day,” linking the white color of the sweets with a reciprocal gesture after Valentine's Day. The idea helped inspire the broader White Day tradition.

White Day was first celebrated in Japan in 1978. It developed as a commercial counterpart to Japan's distinctive Valentine's custom, in which women and girls commonly give chocolate to men on February 14. On March 14, men return gifts to those who gave them Valentine's presents.

Ishimura Manseido is often confused with larger confectionery companies such as Fujiya or Meiji, which also helped popularize Valentine's and White Day products. The company is sometimes written as “Ishimura Manseido” or “Ishimuramanseido”; these refer to the same Fukuoka confectioner in this context. The original marshmallow campaign did not mean marshmallows remained the only acceptable gift: white chocolate, candy, cookies, flowers and other presents later became common.