> Men are supposed to reciprocate on 14 March on White Day – an event dreamed up by chocolate makers in the early 80s to boost sales.
Japan seems to have been especially susceptible to the power of suggestion by commercial entities. It was also the case with diamonds [1]
> Until 1959 the importation of diamonds had not even been permitted by the postwar Japanese government. When the [marketing] campaign began in 1968, less than 5 percent of Japanese women getting married received a diamond engagement ring. By 1972 the proportion had risen to 27 percent. By 1978, half of all Japanese women who were married wore a diamond on their ring finger. And, by 1981, some 6o percent of Japanese brides wore diamonds.