The campaign to internationalize the diamond invention began in earnest in the mid-1960s. The prime targets were Japan, Germany, and Brazil. Since N. W. Ayer was primarily an American advertising agency, De Beers brought in the J. Walter Thompson agency, which had especially strong advertising subsidiaries in the target countries, to place most of its international advertising. Within ten years, De Beers succeeded beyond even its most optimistic expectations, creating a billion-dollar-a-year diamond market in Japan, where matrimonial custom had survived feudal revolutions, world wars, industrialization, and even the American occupation.
Until the mid-1960s, Japanese parents arranged marriages for their children through trusted intermediaries. The ceremony was consummated, according to Shinto law, by the bride and groom drinking rice wine from the same wooden bowl. There was no tradition of romance, courtship, seduction, or prenuptial love in Japan; and none that required the gift of a diamond engagement ring. Even the fact that millions of American soldiers had been assigned to military duty in Japan for a decade had not created any substantial Japanese interest in giving diamonds as a token of love.
J. Walter Thompson began its campaign by suggesting that diamonds were a visible sign of modern Western values. It created a series of color advertisements in Japanese magazines showing beautiful women displaying their diamond rings. All the women had Western facial features and wore European clothes. Moreover, the women in most of the advertisements were involved in some activity -- such as bicycling, camping, yachting, ocean swimming, or mountain climbing -- that defied Japanese traditions. In the background, there usually stood a Japanese man, also attired in fashionable European clothes. In addition, almost all of the automobiles, sporting equipment, and other artifacts in the picture were conspicuous foreign imports. The message was clear: diamonds represent a sharp break with the Oriental past and a sign of entry into modern life.
The campaign was remarkably successful. Until1959, the importation of diamonds had not even been permitted by the postwar Japanese government. When the campaign began, in 1967, not quite 5 percent of engaged Japanese women 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; by 1981, some 60 percent of Japanese brides wore diamonds. In a mere fourteen years, the 1,500-year Japanese tradition had been radically revised. Diamonds became a staple of the Japanese marriage. Japan became the second largest market, after the United States, for the sale of diamond engagement rings.
In America, which remained the most important market for most of De Beer's diamonds, N. W. Ayer recognized the need to create a new demand for diamonds among long-married couples. "Candies come, flowers come, furs come," but such ephemeral gifts fail to satisfy a woman's psychological craving for "a renewal of the romance," N. W. Ayer said in a report. An advertising campaign could instill the idea that the gift of a second diamond, in the later years of marriage, would be accepted as a sign of "ever-growing love." In 1962, N. W. Ayer asked for authorization to "begin the long-term process of setting the diamond aside as the only appropriate gift for those later-in-life occasions where sentiment is to be expressed." De Beers immediately approved the campaign.